Thanks to Professor Rick Keil and his UW Oceanography 409 class on Marine Pollution, I had a chance to go back through the data archives and review the research progress made over the last decade by Beam Reach students and faculty. Below is the talk I’m giving today in Rick’s class to wrap up their study of underwater noise pollution in the marine environment.Read More
While we continue spending this summer analyzing data we’ve collected over the last ~10 years, we’d like to recap what we accomplished last summer. This post is co-authored by Scott Veirs and Beam Reach alum and 2012-2013 intern Breanna Walker.
In 2013, Beam Reach collaborated with The Whale Museum and Lime Kiln State Park by maintaining long-term research projects at the lighthouse, and by mentoring a summer intern: Beam Reach alum Breanna Walker. It was Bre’s second summer studying the role of vessels in generating underwater noise and their potential effects on the behavior of Southern Resident killer whales (SRKWs) as they pass by Lime Kiln (Whale Watch) State Park on the west side of San Juan Island (WA, U.S.A.). Here, Bre and Scott provide first a synopsis of our research and education efforts at Lime Kiln during the summer, and then an overview of our long-term research activities at what we like to call the “Lime Kiln Acoustic Observatory.”
Summer 2013 research & education
Despite the fact that SRKW activity was slower throughout summer 2013 than previous years, research and education was in full swing from June through September at Lime Kiln Acoustics Observatory. Bre spent the summer at Lime Kiln waiting for J, K, and L pod to enter Haro Strait in pursuit of salmon. Thanks to Jason Wood of SMRU Ltd. setting up continuous recording of the hydrophones, we were able to obtain a larger sample of early morning and late night SRKW recordings. These 24/7 recordings supplemented the surface behavior observations and vessel monitoring efforts that Bre undertook during daylight hours. Bre also worked with Jason on a project for SMRU Ltd., localizing SRKW calls from the 2012 season to determine their source levels.
Summer started off with a bang as there was a lot of whale activity in late May and early June at Lime Kiln as we were expecting. However, all the early excitement was followed by an abrupt drop in sightings. Anomalously low prevalence persisted in June and continued for the majority of the summer. After nearly an 11 day stretch with only one sighting of whales, the L22’s (a sub-group of L Pod) provided a unique opportunity for data collection on June 21st and 22nd when they lingered on the west side of San Juan Island for a week or so after the rest of the SRKW population was assumed to have headed back out to the open ocean. The L22 sub-group is composed of the female matriarch L22, and her two sons L89 and L79.
These encounters with the L22s were interesting, not just because it was so unusual to have them isolated from the rest of the population. Often at Lime Kiln we observe the whales “shuffling” either north or south, occasionally pausing to forage, but typically moving along the west side. However, in these encounters the L22s seemed to linger in front of the lighthouse, displaying surface behaviors indicative of foraging, often with the primary acoustic signals being echolocation clicks for extended periods of time, rather than vocalizations. After a few days of this behavior, Bre, along with fellow Lime Kiln Researcher Bob Otis and his interns, began to notice that the whales seemed to head north in Haro Strait shortly before or after the tide changed from flood to ebb. The L22s would leave the southwest end of San Juan Island where they had been sighted spending a lot of time near Eagle Cove and Pile Point, and moved north to the Lime Kiln Lighthouse. This behavior was observed for a few days in June, and then again during the first week of July. Just as we thought we had noticed a pattern they went and did the opposite. However, these less-than-usual encounters got the whale community’s attention and everyone was curious as to why they remained in the area around while the rest of the population was beyond the Salish Sea. Of course, now that L79 has been missing since mid-summer last year (2013), these encounters seem even more intriguing. As we move forward with data analysis, we are especially interested in analyzing the days when only the L22s were present.
The “week of whales” — as it was dubbed by the lighthouse crew — was July 8-12, 2013. During these four days all three pods (a superpod) passed by the lighthouse numerous times. The SRKWs were not sighted again at the lighthouse for another 26 days, with the exception of two encounters with K pod on July 19 and 20. During that time there were two Transient pass-bys, which were recorded during Jason’s data collection for a SMRU project, in which we were recording 24/7.
The summer continued on in a dry spell of sorts. It seemed that the SRKW spent more time out of Haro Strait than they did in, and when the whales were present on the west side, they did not frequent the lighthouse as often as was expected. As of July 26th, 2013, Bob Otis had documented only 17 whale days, less than 50% of the 35 days recorded as of July 26th, 2012. This pattern continued into the month of August.
Despite the lack of whale activity at Lime Kiln last summer, visitors still frequented the lighthouse. In September, Bre worked as a naturalist for The Whale Museum, educating visitors about the whales, salmon, and the Salish Sea ecosystem. The lack of whale activity at the lighthouse frustrated many visitors, however it opened up great conversations about the ecosystem dynamics and the importance of salmon and clean waters for the whales. Overall, it was an educational field season, sparking both concern and curiosity for the future of the Southern Resident Killer Whales, the salmon, and the rest of the Salish Sea Ecosystem.
Links to meta/data —
Long-term research progress
Throughout 2013, Beam Reach maintained a Vemco VR2W fish tag receiver as part of a collaborative resident Chinook salmon (black mouth) tracking project with UW & NWFSC. The receiver was deployed adjacent to the long-term Lime Kiln hydrophone using an existing cement mooring anchor. It was serviced by David Howitt & Jason Wood on 9/13/2013 during a dive in which #110849 was recovered (having been deployed on 4/12/2012) and #102782 was deployed. Link to field notes and metadata. While the grant has ended (most San Juan equipment was recovered in late 2013 or early 2014) Beam Reach is helping to analyze the data and is maintaining a VR2W receiver at Lime Kiln in 2014.
Beam Reach helped maintain the calibrated hydrophone system throughout 2013, both to support the Salish Sea Hydrophone Project and to continue measuring received sound pressure levels of passing commercial ships. Although no new funding was available from NOAA in 2013, Beam Reach paid sub-contractor David Howitt to service the bottom-mounted hydrophone.
As part of the ship noise project, Scott and Val collaborated with Jason Wood of SMRU Ltd. Beam Reach supported the archiving of AIS data in 2013 for passing ships with software written by Val Veirs. The data set now encompasses 31 months from Mar 2011 – Oct 2013 and has been analyzed. We are submitting a paper summarizing noise from about 1500 unique ships in spring-summer 2014.
Finally, Beam Reach continued to maintain the live streaming hydrophone system at Lime Kiln with our partners. While the number of entries for Lime Kiln in our citizen science log (97) was only down ~70% from 2012 levels (325), this reduction in one proxy for listening effort was countered by a rise in another — the number of “hearings” reported on the Orca Network Facebook page. An observational highlight of 2013 from the nearby Orcasound node of the Salish Sea Hydrophone Network was humpback vocalizations (feeding calls, according to Jared Towers) heard for the first time in Haro Strait on October 13, 2013 and recorded by Jeanne Hyde.
Unlike in previous years Beam Reach did not deploy other scientific instrumentation at Lime Kiln in part because we did not run spring or fall undergraduate programs in 2013. Pending renewed funding and educational programs, we will continue to propose new studies using: the existing and new live streaming web cam, our cabled underwater video camera, oceanographic instruments, and a thermal imaging camera.Read More
Parker MacCready (with Matthew Alford)
Observations of flow and mixing in Juan de Fuca Canyon
Pacific water on the continental shelf exerts strong control over Salish Sea productivity, hyposia, and acidification. It is the most important source of nutrients for Puget Sound by a couple orders of magnitude.
The problem is that the Pacific water properties vary strongly with depth. There’s high oxygen water near the surface (DO as high as 110 near 150m) and low oxygen water below (DO ~50 at 800m).
The water enters the Strait of Juan de Fuca via the Juan de Fuca canyon, an understudied region
(see Glenn Cannon, 1972) that cuts across the continental shelf. It’s deep enough relative to the shelf that the inflow can move up the canyon (moving east-northeastward at about 40 cm/s, independent of the tidal state) underneath the surface current on the shelf (typically southeastward flow).
The along-canyon flow gets up to 75 cm/s. As it moves over sills, internal lee waves form that have amplitudes of up to 80m.
ROM model runs show inflow across shelf is primarily via the canyon:
The impacts of upwelling ocean acidification and respiration on aragonite saturation along the WA continental margin
Due to upwelling we are seeing pH conditions that won’t be seen the global surface ocean until the end of this century. The upwelling low O2 water also has high pCO2, low aragonite saturation state, low pH for water >80m depth.
Feely described a new model that can predict water properties 6 months in advance, a tool which could be very valuable to Salish Sea shelfish growers.
Local respiration uses up the (already low) oxygen and increase pH as the water flows in. This can result in anoxic events downstream.
What forces the inflow? Wind from the north!
Ref: Alford and MacCready (2014) Flow and mixing in Juan de Fuca Canyon, Washington. Geophysical Research Letters, 41.
Rob Fatland is talking later about using ROM to visualize the flow of water across the shelf, primarily via the canyon.
The transport observed is about equivalent to the Amazon River, 200,000 m^3/s, easily enough for the Salish Sea “estuarine circulation” about 30,000 m^3/s.
Christie McMillin (Marine Education and Research Society mersociety.org)
Anthropogenic threats to humpback whales in the Salish Sea: insights from northeastern Vancouver Island
2012 Juvenile humpback stranded (long line entanglement)
2013 photographs (by Mark) indicate that it was a high recent year (along with 2011; nice graph)
1985 Merilees documented two periods of whaling in the Strait of Georgia in the late 1800s. Place names like Blubber Bay reflect this history.
Northeast Vancouver Island had whaling as late as 1968 and many humpbacks were taken in the 1950s on the west side of Vancouver Island.
Since 2006 they have documented 8 vessel strike injuries. Since 2009 there have been 5 witnessed cases of entanglement in prawn gear (3), crab gear (1), and seine net (1). In 4 of 5 entanglements, the whale was disentangled.
We can estimate total (non- + witnessed) entanglements by photographing leading edge of tail stock. This method suggests that 9 additional entanglements have occurred in our study area.
There are concentrations of humpback distributions northeast of Hanson Island, while much lower densities occur in Johnstone Strait (particularly SE of Hanson). This observation informed new signs warning vessel operators of the high density areas.
Is you witness entanglement or ship strike, DFO has a hotline, but with a VHF you can call the Coast Guard.
Jared Towers (DFO/Marine Education and Research Society)
New insights into seasonal foraging ranges and migrations of minke whales from the Salish Sea and coastal British Columbia
Minkes do breach!
Highest distributions are on west side of San Juan Island, the banks, and Race Rocks, as well as North Vancouver Island. Lower densities further north and on the outer west coast of Vancouver Island. Despite effort, none were observed off Nanaimo area in the Strait of Georgia.
Strong seasonal distribution, peaking in July. No sighting during ~Oct-Mar.
Previous research: Dorsey et al., 1990. Rep Int. Whal. Commn. Special Issue 12.
Intra-annual movements occur spring-to-summer and summer-to-fall suggest migration. Ecological markers (e.g. scars, swordfish beaks embedded in blubber, diatom coatings or barnacles, cookie cutter shark bites, lamprey scars, Xenobalanus colonizing trailing edge of fins [occurs in tropical east Pacific]). Ref: Towers et al. (in press) Cetacean Research & Management (?)
Prey seems to be juvenile herring and juvenile and adult sand lance. We observe bait balls in the NVI and they may occur in the SJI area, too.
Marla Holt (recording in .mp3 format)
Using acoustic recording tags to investigate anthropogenic sound exposure and effects on behavior in endangered killer whales
Goals: quantify noise that individual SRKWs experience; determine relationship between vessels and their attibutes and received noise levels (RL); investigate kw acoustic and movement behavior during foraging.
Digital Acoustic Recording Tags (DTAGs) have two hydrophones (one for background noises, one for KW signals), as well as orientation and movement sensors. We have 3 field seasons of data so far (Sep 2010 [before 2011 vessel distance increase from 100-200 yards], Jun 2011, Sep 2012) and plan more deployments this year. 23 tags on all three pods.
Animation of a 7-hour tag in Haro Strait SE down Haro canyon, across to Salmon bank, south along its western edge, and then across to ENE Hein bank.
Received levels: RMS averaged over 1 sec in dB re 1 uPa, 1-40kHz band. 2768 measurements of RL (w/o flow noise or whale signals), min 88 dB (3 vessels 2 stationary 1 slow (0-2) kts; Max 141 dB large fast vessel (ferry passing less than 300m from whale!) Julian Houghton’s theses working up predicted noise levels and finding speed and (size, distance??) are most important factors in RL.
Variations in pitch and roll may indicate foraging changes, but few prey samples have been acquired during focal follows with DTAG deployments.
We have documented the iodiverstiy of Salish Sea in two databases:
~82 references used to assign 2,280 species to for ecosystems
Gatydos et al. 2008, 2011; Cowles 2005
Fish completed; birds and marine mammals need work; many invertebrates.
The full fish list is at — http://www.fishbase.ca/trophiceco/FishEcoList.php?ve_code=1067
These data (particularly the trophic pyramid, as well as the “1-click ecosystem routine’) should help researches build ecosystem models. 68% of fish species have biological data in FishBase. There are at least 12 species that are commercially important that don’t have life history data, so they could not be included in the reslience estimations.
There are efforts to cross-reference with the barcode of life movement.
Common risks among declining marine predators suggest ecosystem change
39 taxa of wintering birds in 8 Salish regions and three depth categories
The birds most likely to undergo a decline (based on their model) were the diving birds without local breeding colonies. Across categories, decline probabilities are higher in the birds that eat fish (vs non-fish eaters).
Why are diving birds over-wintering less in the Salish Sea? We suspect that this is because there have been long-term decreases in the forage fish abundance in the Salish Sea. (Some studies have shown concomitant increases in over-wintering populations in California.)
One idea is that the specific power required to maintain a certain air speed is much higher for diving birds. (Nice use of archive.org videos embedded in slide to show difference in flapping frequency in puffins vs frigates.)
Conclusion: Salish Sea birds are shifting wintering feeding ground as a result of lack of prey.
A century of change in trophic feeding level in diet specialist marine birds of the Salish Sea
Western Grebes have declined by 97% in 40 years here and increased 230% in southern CA. Pacific sardines were extremely abundant before being overfished, but the have come back dramatically since the 1980s (Ref Hill, 2010?)
Murrelets in BC have gone from ~500k to 50k population and were studied isotopically using historic samples (feathers formed early in year [condition prior to breeding]) from museums around the world, including bird collected by Vancouver (Norris et al. 2007, Journal of Applied Ecology). The dN15 decline they observe suggests a decrease in trophic level of the murrelet diet from mainly fish to mainly euphausids. Fecundity vs bird count data, suggest that forage fish abundance may be limiting reproductive rates.
Even glaucus winged gulls are in decline. Mondarte populations down from ~3000 to ~900. Average age size is also decreasing (Blight, 2011). The isotopic decline in gull feathers is consistent with the murrelets.
The western grebe is a herring specialist, but isotopic data from grebes have maintained diet (on herring) but most have left the Salish Sea.
Persistent organic pollutants (POPs) in the Puget Sound ecosystem: An evaluation of POPs in fecal samples of Southern Resident killer whales
247 samples in final analysis, including toxicants, hormones, and genotyping
Toxicant results: dried fecal samples vs blubber samples from same whale (30 whales) show strong corrleation; unprocessed (undried) fecal samples vs blubber also highly correlated.
- Higher ratios of ppDDE/sum(4PCB) are highest in L, and secondarily K pods relative to J pod
- Females with >1 calf have lower 2-5x toxicant loads than juveniles, males, and post-reproductive females (who have the highest values)
Graphs of Columbia and Fraser Chinook returns show a ~2 month gap during which there is evidence that toxicant are being mobilized from their lipid stocks.
Ratio of sum(PBDE)/ppDDE shows an increasing trend (2010-2013) suggesting that PBDEs are bioaccumulating.
Next steps are to look at relationships between toxicants and hormone. A pregnancy test has been developed which could be used to assess reproductive success (and hypothetically may be influenced by toxicants).
30 minute discussion (.mp3 format) at end of Session on “Marine birds and mammals of the Salish Sea: identifying patterns and causes of change – II”
- Sustainability Ambassadors
- Martha Kongsgaard, The Moibus strip of science and policy in ecosystem recovery (.mp3 format) [note: Comparing the RMS background noise levels before and after Martha sang to the over-chatty crowd of ~500, there was a 6 dB drop!]
Friday May 2, 2014
The 2013 State of the Sound Status of the ecosystem
PSEMP = Puget Sound Environmental Monitoring Program works with partners to monitor and report conditions and assess restoration efforts. The Puget Sound Vital signs are one tool used to assess ecosystem conditions. Such assessments go back many years (e.g. “Puget Sound’s Health” 1998) and should be continued.
Vital Sign characteristics:
- The “wheel” is fundamentally a communication device, designed for a wide audience (simple, distilled, appealing)
- Indicators founded in science, prioritizing: good surrogates for ecosystem conditions; available historic data; quick response to ecosystem change (including restoration efforts)
- Connections to recovery goals (with both baselines and targets)
Graphs and interpretation of trends in them are simplified into a simple progress scale (with baseline at center, target delineated, and % change indicated by a marker of current conditions.
As of the end of 2013, a few vital signs showed progress, some have lost ground (e.g. orcas), and many that are far from the 2020 targets. One concern is a need for more short-term, responsive indicators.
2013 State of the Sound: Accountability and funding of Puget Sound recovery
As of Sep 2013, 68% of the 2012 near term actions were on plan or complete, 12% were off-plan, 7% had serious constraints, and 12% were not started. The primary cause of delays was lack of funding. In both 2012 and 2013 there were funding gaps of 100’s of millions of dollars.
The Action Agenda Report Card gets updated quarterly and automatically as partners report in. These online data show that the number of complete Near Term Actions (NTAs) is rising overall (2012Q3-2014Q1). Shellfish actions are a good example of steady progress to completion.
Eyes Over Puget Sound: Producing validated satellite products to support rapid water quality
RDI workhorse (300 kHz ADCP) on WA State ferries
Victoria Clipper samples every 5 secs (~100m), 80 mile transect 4 x /day, (T,S,Chl)
MERIS ocean color satellite (2000-2012) combined with others, e.g. LandSat (2000-present, 30-500m resolution nearshore; >1km coastal/offshore)
To ground-truth, they used partial least squares regression (commonly used in chemometrics, bioinformatics when many parameters are available and correlated). Working towards an operational workflow.
Open source mapping to improve data sharing: Environmental response management application
Web-based mapping tool — Environmental response management application (ERMA) — aiming to make data sharing between agencies, coordinated through UW Tacomea’s Puget Sound Institute. Now trying to complete after starting before Deep Water Horizon spill distracted. Real-time data (e.g. from AIS, NOAA weather buoys, NANOOS), forecast data (weather?), and base maps and database (e.g. Marine Protected Area portal, Burke Herpetology collection, Encyclopedia of Puget Sound, NatureServe?, Audubon data on Canadian watersheds and bird distributions) goes to ERMA Data Center and is accessible from oil spill response Command Center.
Whale telemetry data can be imported and animated. Satellite tag example.
Upcoming events: August 2014 drill; CANUSPAC.
Rob Fatland (Microsoft Research)
Ebb and Flow: What we learn from visible circulation patterns in the Salish
All technological problems are solvable. You just need to find the write person.
Geophysicist (glacialogist turned oceanographer). Microsoft offering 1 free year Azure cloud computing, but the challenge is finding the right collaborators to help manage data. Cyberinfracture involves registering and communicating about data sets. Machine learning is the likely way to distill big data from the growing cyberinfrastructure.
Worldwide telescope is the core of http://layerscape.org
Wade Davis, UBC
The critical importance of preserving ecosystems for current and future generations & the significance of ancient wisdom
Audio recording ( .mp3 |.ogg | .flac )
The Herring School: Long-term perspectives on herring in the Salish Sea and beyond
At 179 sites along BC coast and in WA (inland) herring was the major commonality (all but 2 sites on N Coast) and was extremely prevalent in the Salish Sea. % of herring relative to other fish (based on bone archealogy) varied from 80% in northern Strait of Georgia to 20% in Puget Sound. Distance from herring bone sites to existing herring spawning sites is <~2km.
Visible foodstuffs in a drawing of part of Chief Maquinna’s house include 2675 herring/anchovy, 20 flatfish, 10 greenling/cod/hake!
Can we have our herring and eat our salmon too? A qualitative approach to modeling trade-offs in the Puget Sound foodweb
Foodweb figure coming…
J(oan?) Drinkwin (Northwest Straits Derelict Fishing Gear — winner of the 2014 Salish Sea Science Prize! http://www.derelictgear.org/ )
Observed impacts of derelict fishing nets on rocky reef habitats and associated species in Puget Sound
PS has lots of derelict fishing nets because of abundant rocky outcrops and long-history of salmon fishing. Nets located with side-scan sonar and reports from divers, etc. All material removed by hand, not grapnel. 4467 gillnets removed (95% of those located), 168 purse seine (10?%). 672 acres of habitat restored as of March 31, 2014. %5 of fish found dead in nets are rockfish (including one canary rockfish).
Next steps are to continue removal, including with expanded fleet. Need funding to go deeper than 105′.
Annual net loss is 10-30 nets and our new program aims to keep new nets from accumulating in the environment, including education and tools to increase (often mandatory) reporting by fishers. Of 24 reports in pilot program, 10 were removed, 7 had unknown location, 2 not found, 4 not derelict fishing gear, 1 in Columbia River.
This afternoon I’m giving a talk at the 2014 Salish Sea Ecosystem Conference in which I present our estimates of sound pressure levels from commercial ships in Haro Strait, the core of the summertime critical habitat for the Southern Resident killer whales. I also take a first look at noise impacts of the current tanker and bulk carrier fleets and ask how those impacts may change if a suite of proposed fossil fuel export facilities are added to the Salish Sea.
For this talk, I’m excited to have experimented with in-browser HTML5/CSS methods of presenting (alternatives to Power Point and Prezi). There are a bunch of interesting new players like SlideCaptain (good for equations), but I settled on Emaze because of how gracefully it handled embedding of sound and video.Read More
Sponsored by the Puget Sound Partnership and organized by Orca Network, the Salish Sea Association of Marine Naturalists, and The Whale Museum, this workshop preceded the 2014 Salish Sea Ecosystem Conference.
Daniel Schindler, UW
The “Effects of salmon fisheries on SRKW” report
12:09 Starts with introduction of the science panel members
12:12 We were charged with evaluating the BiOp’s “chain of logic linking Chinook salmon fisheries to population dynamics of SRKW”
Population decline in both NRKW and SRKW was coordinated in late 1990s.
We were blown away by the quality of SRKW demographic data. This is probably one of the best-studied wildlife populations in the world.
Eric Ward estimated growth rate (lambda) as 0.99-1.04 (mean ~1.017, or ~1.7% exponential growth) for J/K pods and 0.985-1.035 (mean ~1.01, or ~1% exponential growth). The overall SRKW rate of 0.71% per year might increase to ~1%), but fisheries management changes are unlikely to raise the growth rate to the recovery goal.
There are 1000s of papers about Chinook salmon, but less is know about Chinook topics relevant to SRKWs. Listed 3 shortcomings.
Kope and Parken summarized Chinook trends for specific stocks important to SRKW. Coastwide there has been a modest decrease in recent pre-harvest Chinook abundance. There isn’t much room to lower commercial fishing in a meaningful way (e.g. decrease harvest of 20%).
Correlations between SRKW vital rates and Chinook abundance depends on abundance measure chosen. Mortality of SRKW should scale non-linearly with salmon abundance, but the existing correlations are linear.
Bain: Why weren’t acoustics impacts of fishing vessels considered? A: I don’t know. Perhaps because available data did not include fishing boats.
Felleman: Were analyses done using only Columbia Chinook? A: No, but you should email Eric Ward about that. You should also be careful about interpreting correlations as causal relationships. If you look for correlations from 50 different salmon populations, you’ll find strong ones just through random chance.
Elizabeth Babcock, NOAA
The intersection of salmon and orca recovery
Focus is on Puget Sound stocks. Locally-developed recovery plans for Puget Sound Evolutionary Significant Unit (14 watersheds from Neah Bay to Point Roberts; 22 populations) reviewed in 2005, then adopted plan in 2007, and are now implementing with partners.
70% of our estuary habitat area in Puget Sound have been lost…
Lynne Barre, NOAA
Mike Ford, NOAA
Salmon recovery and SRKW status
Noren (2011) suggest SRKW metabolic demand is 12.6-15.1×10^6 kcal/day =~1000 Chinook salmon/day
Ward looked at all available Chinook time series and found many correlations, including between runs, but the strongest correlations were not with the Fraser nor the Columbia.
Interesting population projection figure from Ward (2013)
Post-workshops we have been looking at trends in other marine mammals: AK and NR KWs increasing, CA sea lions now ~6x 1975 levels, harbor seals 6-8x…
Overview of salmon status
- Historic Chinook salmon abundance figure (compiled Jim Myers, NWFSC): Biggest reductions were in Columbia (~-3-5x) and Central Valley (~-3-4x)
- Bonneville time series (1938-2014) shows abundance declines happened a long time ago (pre-dams!). 2014 levels approaching 1888 average levels!
- A lot of the historical losses are due to extirpations (Gustafson et al., 2007): biggest extinct populations were in Columbia above Grand Coulee and Snake
- Run timing changes: Columbia example — ~10x reduction in interior run (above Bonneville) from ~2.5 million to ~200k.
- Hatchery production rose from 1950 to peak in mid-80s and in 2000 was near 1970s levels (Naish et al. 2007)
- Puget Sound historical abundance is ~700k (based on cannery pack in 1908); current wild escapement is ~50k; hatcheries add ~300k.
- Habitat: 31,000 projects completed at 51,000 locations throughout Pac NW. Over $1 billion spent on restoration to date.
- Hatcheries: overall reductions in hatchery releases in last few decades, and limiting genetic impacts on wild fish. One example of reductions to near zero is on OR coast…
- Harvest: easiest to change and responsive; examples of successful catch reductions are Hood Canal summer chum. Coastwide harvest % has decreased by ~factor of 2 over last 30 years
- Hydro: improved fish passage, predator control, spill, barging; dam removal on Elwha, Condit, Rogue, Sandy, Hood River
- Heat: potential effects of climate change mostly not great for salmon; summarized by Stoute et al. 2010 and Wainwright and Weitkamp in prep
- Orca recovery spending: FY12 1.2M on science/research; ~300k on management/conservation
- Orca salmon spending: FY12 600M!! Columbia only is 450M!
David Troutt, Director of Nisqually Natural Resources (for 35 years) and Chair of SRC (=Salmon Recovery Counci)
WA State salmon recovery — How we work together
State broken into regions, each with their own recovery plans (developed through the “WA way” involving many stakeholders, endorsed by Feds). Go to RCO web site for more information.
Study completed in March 2011 estimated costs of all planned regional plans is ~$5.5 billion. Funds dispersed through Salmon Recovery Funding Boards established in 1999. Funds come from PCSRF and others… Note: it is a LOT cheaper to protect than to restore…
10% of Federal grants must be used for monitoring. Example: About 80% of Nisqually outgoing smolts remain in estuary; 20% seek pocket estuaries elsewhere, but we see almost no returns of fish using the latter strategy.
There is a problem with marine survival in Puget Sound. We see 95% mortality of tagged out-going smolts between the Nisqually and Port Angeles. We’re confident that the estuary is in much better shape and 77% of the mainstem is in permanent stewardship, but we’re not seeing any result in the numbers of returning adults!
2:15 Tribal perspectives
Story: a generation of Nisqually fishers have never caught a steelhead. Annual catches of ~2k by tribes and ~2k by recreational fisheries collapsed (in 1990s?) to total run of ~500, a condition which persists. The treaties have not been withheld (and the tribes have not “shot at y’all in a long time”).
We need to work together towards ecosystem restoration. The tribes are interested in actions related to all H’s. The tribes have been working with the State to adapt how we run hatcheries to support harvest, but also be consistent with recovery goals. The North of Falcon process is part art, part science, but it is transparent and it works.
Rich Osborne, North Pacific Coast Lead Entity Coordinator (WRIA 20)
WA Sustainable Salmon Partnership — Salmon recovery on the WA coast
What’s unique about the outer coast in terms of salmon restoration?
- All 5 salmon species and steel head; none are listed except Ozette sockeye.
- Large areas are encompassed within tribal lands, which allows alternative restoration strategies.
- Almost no people! Only 7000 people on coast with no residential areas
- Large portions of watersheds in National Park, other large areas in National Forests.
Formed a non-profit to raise money beyond the SRFB: the WA Coast Sustainable Salmon Foundation. WRIA 21 = Quinalt; WRIA 22&23 Grays Harbor; WRIA 24 Pacific County.
- Goodman Creek road decommissioning (4 miles of road and fill removed)
- Quinalt: old logging road and fish passage blockage removal — facilitated by ability for tribe to control local decisions.
- Grays Harbor: huge estuary Chehalis has spectrum of impacts (industrial, logging, headwaters in National Park), but again not many people
- Pacific County (Willapa Bay): huge estuary w/few people; mostly Weyerhauser timber operations between pristine upper watersheds and the ocean.
28 Chinook stocks returning only 30-40,000, but could be 100s of 1000s…
An additional 12 million hatchery fish released from coastal watersheds per year
Salmon stronghold study areas (circa 2006)
Jeannette Dormer, Puget Sound Partnership
Salmon Recovery in Puget Sound
In contrast, there are 4.1 million people in the Puget Sound region: 12 counties, 20 large cities, 100 cities total, 17 treaty tribes, many NGOs; 15 lead entities; Puget Sound Salmon Recovery Council (not the Partnership) is policy body to oversee implementation of the PS salmon recovery plan.
6 salmonid species, 3 listed under ESA (PS Chinook threatened in 1999, Hood Canal summer chum threatened in 1999, 2007 Puget Sound steelhead).
Salmon recovery success example: Puget Sound Acquisition & Restoration (PSAR) Fund. Regional priority list; increased from $15 million to $70 million appropriated for 2013-2015 biennium
- 100s of acres of estuary restoration in Snohomish and Skagit rivers
- Elwha dry lake bed reforesting
- 3+ acres eel grass on Bainbridge
- Seahurst seawall removal and restoration
Intersection with orca…
Jacque White, Exec. Director of Long Live the Kings (used to work at P4PS and Nature Conservancy)
Salish Sea marine survival project
Many partners supporting the coordinating organizations — Long Live the Kings in U.S. and Pacific Salmon Foundation in Canada
“Puget Sound salmon are sick and we don’t know why…”
- Coho marine survival declined sharply in 1980s from ~3% to <~0.5% and has persisted, while during the same period (1974-2007) WA/BC coastal survival has been fluctuating around a mean of ~0.5%. There are similar trends for steelhead and Chinook.
- Declines in Fraser sockeye, steelhead, herring spawning areas, forage fishes, hake, lingcod
- Rises in Harbor seals, lags, temperatures, and human population
- Little effort to integrate research efforts
- Now seeing economic impacts on humans (sports fishing, tribes, First Nations)
- 2007 State of the Salmon in 2007 focused on interactions of wild and hatchery salmon
- 2012 fall workshop led to idea of a transboundary project to increase survival in the Salish Sea, improve accuracy of adult return forecasting, and assess success (or failure) of existing salmon recovery efforts.
- 2014 Comprehensive planning
- 2015+ Implementation of research
Hypotheses (trying to identify factors that control salmon and steelhead survival that can be managed)
- Bottom-up processes (PDO, environment, forage fish changes to which salmonids haven’t been able to compensate)
- Top-down (predation…)
- Other factors (toxics, disease…)
- Focus on juvenile fish
- Predation of seals on steelhead
5:14 Final comments and next steps (also included in audio recordings)
The year 2013 was an exceptionally unusual one in the world of southern resident killer whales and Pacific salmon. Most noticeably, the southern residents returned to the Salish Sea later than normal, raising concerns among conservationists. Throughout the summer, researchers and whale watch operators noted that the whales were present less than normal and the duration of their visits to the Salish Sea were abbreviated.
Meanwhile, the Chinook salmon runs on the Fraser plummeted while 80-year record returns were counted on the Columbia at the Bonneville dam fish ladder. Combined with new evidence from satellite tags that the southern residents are focused on Columbia salmon during the spring months, the sighting patterns of 2013 may indicate a transition for the urban estuary known as the Salish Sea — from one with “resident” orcas to one with southern “transient” fish-eating orcas.
Killer whale trends
Based on data from the Orca Network sighting maps from the past decade (see figure below), records were set or tied in 2013 for the least number of days spent by southern residents in the historic core of their summer habitat (the west side of San Juan Island in Haro Strait). The SRKWs were seen only once in March and not at all in April. Even more shockingly, they showed up only 5 times in May (a record low) and were observed 15 times in June, a low level not seen since 2001.
The same data show downward trends in monthly sightings over the last decade. With the exception of a high in 2011, the March prevalence has been flat or decreasing. There are stronger, more continuous downward trends in April and May sightings.
We used the OrcaMaster database maintained by The Whale Museum to look for trends in sighting “gaps” — the number of consecutive days between sightings of J pod members within the Salish Sea. Val plotted running averages of 2013 gaps versus a historic average (1992-2012) and found that in the spring of 2013 sighting gaps were 2-5x longer than the average. Only during and after September of 2o13 did the gap return to a normal duration. (Maybe we should look at trends in Salish Sea chum run?)
One way to characterize the foraging conditions the SRKWs experienced in 2013 within the Salish Sea and on the outer coast is to examine the Chinook salmon counts from the Fraser and Columbia rivers. The Albion test fishery on the Fraser provides a proxy for the abundance of Fraser Chinook, the primary prey of SRKWs in the Salish Sea from spring through the summer (Hanson, Baird, Ford, Hempelmann-Halos, Van Doornik, Candy, Emmons, , , , , , , , 2010). The fish counts at the Bonneville dam on the Columbia are a proxy for the abundance of Chinook on the outer coast of Washington.
As marine naturalists like Jane Cogan and Monika Wieland have pointed out, 2013 was an exceptionally bad year for Fraser Chinook returns. The fish arrived late and the cumulative returns were well below this historic average and only slightly better than in the worse year on record, 2012. The highpoint of the 2013 run was the peak around the 3rd week of August that may also be related to a pulse of Chinook recorded in the first two weeks of July off southern Vancouver Island (in the Area 20 test catch fishery).
In contrast, adult and jack Chinook abundance in the Columbia River has been on the rise for the past couple decades, with 2013 standing out as a record-setting year for adult Chinook.
Daily Chinook counts at Bonneville show that while most of the record-setting abundance was due to the fall run, the spring run also had peaks well above the 10-year average.
The spring run passed Bonneville from late April to late May, 2013. This timing is consistent with the timing of the spring Columbia Chinook run in 2012. Since Bonneville dam is about 200 km upstream from the river mouth and adult Chinook swim at about 0.5 m/s, we could expect that the returning Columbia Chinook were in the ocean at least until about a week before they reached Bonneville ( 200,000 m / 0.5 m/s = 400,000 seconds = ~5 days). So where were the southern residents in March and April of 2013, since they weren’t being sighted in the Salish Sea? We don’t know about J and L pods, but the satellite tag deployed on K25 indicates the likely position of K pod (up until April 4).
The answer is: during March, 2013, K25 was spending a lot of time going back and forth along the continental shelf of Washington (and to a lesser extent Oregon) with a track that centered on the mouth of the Columbia River.
We need to know more about when the returning Columbia fish are on the continental shelf and accessible to the southern resident killer whales. But these salmon trends from the region’s biggest rivers combined with migratory patterns of the orcas strongly suggest that the southern resident killer whales may be happy to move their “residence” to wherever the eating is best! Perhaps we are watching them become southern transient fish-eating killer whales?!
Anecdotal observations of orca-salmon interactions
When the fish-eaters were around during the summer of 2013, they displayed some unusually aggressive foraging. A (potential) prize Chinook salmon was taken off a derby fisherman’s line and became the focus of a KPLU radio story and an impressive photo of the one that was eaten away…
This local predation event was a first for Washington State (as far as we know), though it was comparable to one by Alaskan fish-eating killer whales. In the video below, the Alaskan whales were foraging amongst fishing vessels and happened (probably visually) upon a large hooked Chinook. (Mute your speakers if you don’t want to hear angry and amazed fishermen cursing.)
Later in the summer of 2013, back in Washington, a whale watch captain obtained this video of southern resident killer whales pursuing a large (likely Chinook) salmon alongside the boat —
Could these uncommon foraging observations indicate that the southern residents were having a tough time finding enough to eat in the Salish Sea? We’d be interested in hearing from local fishers about how often they’ve had fish taken off their lines by Southern Residents. Monika assures us though that it is common to observe SRKWs pursuing salmon around and underneath whale watching boats, so maybe we should attribute the second video to more typical foraging and take it as evidence that orca-salmon interactions in the fall of 2013 were more typical than earlier in the year.
A couple years ago Val put a bunch of effort into stabilizing a video of some rare southern resident killer whale behavior that Beam Reach observed during our first field program in fall, 2005. In support of an upcoming fundraiser for The Whale Museum, we have uploaded the stabilized version to YouTube and then stabilized it as second time using YouTube’s editing enhancement. (The original, shaky footage is also stabilized as of 2014, but only using the secondary YouTube stabilization.)
We hope the double-stabilized version (embedded below) doesn’t make you too seasick. You may also enjoy the links below and appended background information re-posted from what was originally published at orcasphere.net.
Video credits go to Beam Reach students Brett Becker and Courtney Kneipp. Still photo credits go to the Washington State Department of Ecology and Iris Hesse of the Center for Whale Research. Listen for a very unusual simultaneous call made by many individuals during the last minute of the recording.
- Still photos
- Photo of closest approach before submergence (credit: Center for Whale Research)
- Still photos by Rachel Griffin
- Kathryn’s working directory with metadata, audio, & photos
- Kathryn’s spectrograms
Re-printed blog post from orcasphere.net
Originally posted on May 16, 2006 —
One of the most remarkable behaviors of the southern residents is the “greeting ceremony” in which two groups of orcas line up facing each other and then mingle together. This article describes a similar “ceremony” acoustically and visually (video; photo gallery), and then discusses whether it may have been related to a “greeting,” a “goodbye,” or a more complex combination of activities.
I offer it here in the hope that others who witnessed this particular event may further consider what occurred. Please feel free to comment on this article and/or contribute your thoughts via the discussion forum. Insights from other accounts of different “ceremonies” performed by the southern resident (or other) orcas would also be welcome. Perhaps we will piece together a publishable story?
On October 4, 2005, only a week into a month of sailing with the southern residents, students and teachers of the Beam Reach marine science and sustainability school approached San Juan Island along with members of J and L pods. The Beam Reach research vessel, the sailing catamaran Gato Verde, paralleled the orcas as they moved northward from Salmon Bank along the west side of San Juan Island during the mid-afternoon. In the early evening, starting around 4:30pm PST, the pods began to concentrate within 100 meters of shore below Hannah Heights.
The “ceremony” that we observed (along with Tom McMillen, observers from the Center for Whale Research, and Sharon Grace [and others?]) was similar to “greeting ceremonies” that sometimes occur in the spring as the southern residents return to the Salish Sea from their winter ranges. One group of at least 9 adults and one calf (probably a subset of the group that had been traveling northward with us) congregated within 100 meters of shore ~0.5km southeast of a promontory with abundant driftwood (48o 29.65N, 123o 7.62W). They remained on the surface, gathered into an extremely tight group, traversed the shoreline southward for a few minutes, then doubled back to the north. Meanwhile, a different group of at least 9 adults rounded the driftwood point, heading south, and began to congregate in a rough line just south of the promontory’s rocky bluffs. They, too, remained largely on the surface, drew together in a line, and proceeded slowly southeastward toward the southern group. When they were about 25m apart, the southern group lunged forward, submerged, and quickly met the northern group. The two groups mingled, turning quickly and making brief dives, and remained together for an extended period (at least 15 minutes — we left at ~5:15pm to make port before nightfall — and probably much longer).
The ceremony was documented by Beam Reach with still photographs, digital video, and stereo underwater sound recordings. Preliminary analysis of the still photographs and video suggests that at least J40, J14, and L41 were part of the southern group. Tom McMillen of Salish Sea Charters with Iris Hesse and EEH (??) of the Center for Whale Research (CWR) were drifting near the northern group and photo-identified many of its members. Based on an initial examination of still photographs taken of the combined groups, Dave Ellifrit of the CWR noted that L84, L41, L90, L72, L55, L82+calf, L25 with L41, and Raggedy (K40) were present. Any additional photo-identification (and associated) debate is welcome!
An interesting aspect of this event, first pondered by Tom McMillen (and later discussed with Ken Balcomb and Dave Ellifrit?), is that it approximately coincided with the last time that the matriarch L32 was seen. Earlier in the day (about an hour before the ceremony began?), Tom observed L32 with son L87 and noticed that she was emaciated and had a weaker-than-normal blow. CWR photographs confirm that L32 had a sunken blowhole area (“peanut head”) that day. L32 was not observed after the ceremony and L87 was observed the next day (or maybe 2 days later?) without L32, so L32 is now presumed to be dead. Could we have witnessed a “goodbye” ceremony?
Perhaps, but the CWR photographs reveal that the ceremony also involved foraging (birds hovering over orcas at surface) and sexual activity (sea snakes). Beam Reach video shows traveling behavior, milling, tail lobs, and pectoral fin slaps. There was a lot of acoustic activity prior to the meeting of the two groups, including abundant echolocating and intermittent calls, and an amazing coordinated acoustic event in which many individuals call simultaneously (without an obvious cue).
I’ve created this movie that juxtaposes the best of the Beam Reach video and underwater sound. Please note, however, that I was unable to synchronize the sound and video. I am tempted to associate the simultaneous calls with the dynamic lunge of the two groups together, but (I regret) there is currently no way to know whether that is right. Video footage was acquired by Beam Reach students Brett Becker and Courtney Kneipp. Acoustic data is from 2 ITC hydrophones mounted 1.4m apart on a horizontal pipe at 4.4m depth. (The engine noise at the beginning of the movie is from the Beam Reach research vessel.)
Please don’t hesitate to comment, email, or start a discussion thread if you have information or ideas about this fascinating behavior of the southern residents.Read More
Notes by an oceanographer from an upper trophic (orca) perspective during the outer-coast/less-local/more-regional portion of the annual meeting of the Marine Waters Monitoring Workgroup of the Puget Sound Ecosystem Monitoring Group (PSEMP) at APL/UW on 3/28/14. This meeting is a rare effort and opportunity to synthesize ocean observations from the previous year and across the Salish Sea and outer coast of the Pacific Northwest region (with an over-emphasis on Puget Sound). I was not able to stay for the rapid-fire talks related to plankton & pathogens (e.g. harmful algal blooms) or water quality.
Freshwater inputs — Ken Dzinbal
In long-term medians from rivers across region, the overall long-term seasonal pattern is a dry period in Sep-Oct (extending into late fall for some rivers), then a wet spring with big storm pulses Feb-June. In 2013, Fraser mean daily discharge at Hope (above tidal influence) peaked in late May, ~1 month earlier than historic median.
Fred Felleman mentioned that 2013 was a terrible year for Fraser river Chinook and a bumber year for Columbia Chinook, and that the Southern Resident Killer Whales (SRKWs) responded one would expect for the “best salmon samplers on the planet” — they were rarely sighted in inland waters and tracked often on the outer coast near the Columbia river mouth. PSC Fraser panel is a good source of historic data on Fraser flows.
Boundary conditions & water masses — Skip Albertson
Less upwelling in Aug/Sep; SW winds! Usually we have N winds and upwelling in September, but we almost had down-welling due to unusual winds out of the southwest.
We looked at Pacific Decadal Oscillation (PDO), and index that changes slowly. Initially there was colder water up against the coast, but then offshore waters got warmer and warmer. Overall in 2013, the PDO index was slightly lower than long-term means.
Cha’ba mooring (offshore Washington) — John Mickett
Temperature-Salinity plot for all of Puget Sound shows median values near 11 oC and 30 psu with low (6.5 mg/l) dissolved oxygen (DO) levels. This suggests a stronger-than-usual influence of oceanic water. Christopher Krembs pointed out that the goal is to start looking at Puget Sound water properties in terms of water masses that may traverse the different basins, rather than
The big story on the outer coast in 2013 was the hypoxia. John showed pictures of many dead Dungeness crabs washed up on Ruby Beach. Looking at data from 3 and 84 meters, you see phytoplankton blooms (chlorophyll concentrations up ~20 micrograms/l). In mid-August we saw DO levels drop to ~1 ml/l a level which stresses or kills organisms. At about the same time we saw very unusual warm surface water temperatures (up to 16-18 oC, well above the long-term means of ~12 oC) which were due to the wind reversals that led to stratification and subsequent solar-heating.
Upwelling comes from 30-40m (ref Ryan McCabe) and has much higher DO than what we saw. That’s why we think these low DO events in the shallow water were advected horizontally, having formed somewhere else.
End of May (5/31) and beginning of July (7/1) sees Columbia River plumes in surface waters. Are these related to court-ordered dam releases?
San Juan channel — Jan Newton (slides from 2013 research apprentices)
North station off NE San Juan Island; South station just south of Cattle Pass (tends to picks up Pacific Ocean influence)
Normally, Fraser plume is advected south in the summer and north in the winter, with associated up-/down-welling changes. It creates a strong pycnocline near 30-40m.
Redfield AC (1950) Note on the circulation of a deep estuary: the Juan de Fuca-Georgia Straits
In 2013, TS plots from Centennial calibrated CTD show that 2012 was an anomalously cold year. The 2013 T-S ranges were +1 oC higher, and slightly fresher. In mid-October the cold 2012 water was ~0.5oC lower than long-term medians.
PDO shift from + to – values near 2007 correlates with warmer to cooler transition in inland water temperatures. There are initial hints that during the inland cooler periods we see higher seabird (and other upper trophic level animal?) populations.
Harbor porpoise acoustic studies — Aileen Jeffries
CPODs and land-based visual observations. CPODS for 3 years in Burrows Pass, also at Biz Point and now at PTMSC
Harbor porpoise population plummeted in 50s, were nearly gone in 70s and now seem to be on a rebound.
Acoustic detections from Burrows typically show nighttime peaks of ~50 minutes/hour and 1/10th those levels during the day.
Click rates of 400-600 clicks/s during foraging; about 20 clicks/s otherwise (histogram).
Seasonally they are less present during the summer (low in May/June) than winter at Burrows Pass (based on visual sightings).
Primary prey is herring, smelt, and sand lance. Florian Granger (did PhD in Europe on harbor porpoises) says that they often travel in groups of 3.
What about anchovies and the possible decadal dynamics on the outer coast?
John Mickett asked why the diurnal pattern is so strong in Burrows Pass. Aileen thought that they were targeting animals that follow the vertical migration of zooplankton to surface waters at night, but also suggested day-time boat interference might be a factor (but implied they had not quantified boat traffic). Dzinbal suggested that squid might be following the zooplankton…Read More
During our study of adult salmon movements in the San Juan Islands, we tested a novel method of deploying Vemco (VR2W) receivers. With permission from local land-owners, we used free climbing equipment or pitons to anchor a crab pot line to the rocky shoreline, marked it as fish research to discourage vandalism or theft, and then used it to tether the Vemco receiver mooring to shore. This allowed us to deploy and recover the mooring from a small boat, saving the cost of divers and simplifying the re-location of a mooring.
Tethered mooring materials, methods, and locations
Salmon school passes around the fish tag receiver mooring at Lime Kiln State Park
Project map (Google map in which green markers denote deployed receivers, magenta are recovered from our UW/NOAA collaboration (2011-2013), yellow were planned sites for 2011-12, red are other potential sites, and blue are landmarks):
View San Juan fish tag receiver deployments in a larger map
A typical deployment involved dropping a researcher off on shore. While the boat driver stood off and prepared the mooring, on shore the researcher created a climbing anchor using cracks of convenience in the rocks and/or trees. Aluminum alloy wired nuts, chocks, and hexes were the most common anchoring devices. Both seemed to weather the salt-water environment very well, though the stainless wire rope in the nuts and chocks showed some signs of corrosion after about a year in the field. Once set, the anchor was attached to a length of leaded crab pot line, a float was tied to the end, and the float was cast well offshore. The driver then returned to pick up the researcher and together they retrieved the float. The shore tether was then tied to the mooring and as the boat backed away from shore towards the deployment point, line and anchors were deployed until adequate water depth was attained. Finally, the mooring assembly was lowered into the water and released. (Early on we used a slip line, but eventually just dropped the moorings as they seemed to sink vertically and not too fast.)
A typical recovery also began by dropping a researcher on shore. First the anchor was removed or checked and maintained. Then the tether was disconnected from the anchor and attached to a float. The float was cast offshore, the researcher picked up, and the float brought onboard. Then the dirty work of hauling up the mooring began. A bow roller helped, as did having two people work together. An important innovation was a short piece of PVC slit so that it could be passed around the line and used to strip fouling off as the line was brought aboard. Once the mooring was raised, the receiver could be removed or swapped. Then the mooring assembly could be stored or immediately reused in a new deployment.
With a small boat capable of doing 25 knots on flat water, this method allowed us to service 4-6 receivers per day. At the end of the study, we were able to retrieve 8 receivers in a single day trip beginning and ending in Seattle.
- Galvanic corrosion (between a stainless steel shackle and a length of galvanized chain) caused the loss of Lime Kiln receiver (luckily it was found on a beach near Victoria). Connect the Vemco to the mooring anchor using a single type of metal (e.g. a galvanized shackle).
- Mooring depths should be at least 5-8 meters deep especially in high surge environments. Shallow deployments resulted in the loss of 2 False Bay receivers (one was found on a nearby beach).
- Dive recoveries were required 4 times, primarily because of chafe (Iceberg, Sucia, Sentinel, Patos). Minimize tension and contact with rock edges?
- Human disturbance rare (despite faded labels, only Turn Point and Obstruction were disturbed; neither was removed).
Examples of different amounts of fouling
The amount of marine organisms that colonize the mooring float, receiver, and/or anchor — as well as the line — varied tremendously between sites. Geography and oceanography are likely the controlling factors, but there was some suggestion that deeper deployments had less growth overall, and especially reduced amounts of brown algae colonization.
Unlike diving, this method allows students to assist in deployments and recoveries without specialized training. The method helps motivate new knot tying skills as well as small boat operations.
While Beam Reach students have not yet utilized data from the San Juan salmon tracking study, we hope that the Hydra database will facilitate that. To date, our only student projects using Vemco data came from our own tagging of ling cod at Lime Kiln State Park with pressure-sensing tags and monitoring achieved with a VR100 system.Read More
Yesterday David Howitt and his crack team completed the retrieval of the last couple Vemco receivers that were being used to track adult salmon in our collaborative fish research with UW and NOAA/NWFSC. Here is David’s field report, along with some great photos:
- Boat operator and two divers depart from Roche 1100, return Roche 15:30 – 4 1/2 hours
- 2 Dives, 2 retrievals, pretty straight forward with finding near shore anchor block early in dive at Succia. Sentinel found drifting line, went down to 60 feet and were lucky
- Will deliver pier blocks, Vemcos and tanks to Val tomorrow
- found one weight belt at Succia, lost one knife.
- Succia Vermco SN# 100913
- Sentinel Vemco barnacle encrusted
- Pouring hot tea into gloves really helpedDive stats:
#1 Sucia, 11:57 minutes, 41.56’, 46 degrees in water.#2 Sentinel, 12 minutes, 62.25’, 45 degrees in water.