Concerns about overfishing are a pressing issue. Technological advances, have made fishing industries much more efficient. Fish are caught at greater depths, and in much larger numbers. Some scientists have estimated that as much as 90% of large predatory fish including sharks, swordfish, and cod have been removed from the oceans of the world . With so many large predatory fish having been removed from the ocean it may seem that there are plenty of other fish in the sea, however this is untrue for a growing number of fish populations. Other factors, including pollution, fishing methods, and habitat destruction contribute to the decline of many fish populations, including Chinook salmon.
As we have learned, Chinook are the preferred prey of the endangered southern resident killer whales. These salmon are also listed as endangered. Habitat degredation, genetic and ecological impacts from hatchery production, and impacts from hydropower are factors that put these fish at risk. While Chinook salmon make up 65 % of the southern resident killer whales diet, and are of upmost importance to this population of killer whales, they are also consumed by many other marine animals. As specific fish populations become threatened or endangered, so do the predators that depend on them as a food source.
Understanding relationships between predators and their prey is crucial to maintaining, and sustaining the environment in which all living creatures share. Establishing the importance of all members contributing to an ecosystem further emphasizes the importance of practicing sustainability. It is important to remember that the environment in which we live is delicate and can be manipulated easily. It is up to all members of society to establish methods for fishing that will not devastate the environment in which they live, and share.
As all the 112 Beam Reach students (Sharon, Laura, Hayley, and Charla) can recall the phrase we heard the most was “this never happens†or “this is a firstâ€. After hearing it a few times we decided to keep track of all the so called “firsts†for Beam Reach.
Seeing a fire truck and an ambulance zooming through campus – “This never happens at Friday Harbor Labs!â€
First year observing at Lime Kiln – “You are the first Beam Reach class to be able to use the Lime Kiln as a research base… so now you get to clean the acoustic shed, YEAH!”
Residing in T2 (with carpet) compared to S1 – “This is a first, we have only had S1 in the past…and there is carpet!â€
Most organized and clean group of students – “Your dishes are so organized all the time; this is a first for Beam Reach.â€
Most whale days – “You guys are so lucky this never happens.”
Breaching Southern Resident
Most Dall’s porpoise off the bow – “It’s rare to NOT see Dall’s but never this much.â€
First Canadian – “Charla is the first Canadian to be a part of Beam Reach – CONGRATS!â€
First conference (Salish Sea Ecosystem Conference) – “This is the first time Beam Reach is going to a conference and presenting posters”
Lunch with John Ford – “I bet this is a first for Beam Reach, lunch with a science celebrity… John Ford!”
Most rainbows (single and double) – “Want another Beam Reach first… the most rainbows!”
Students collecting data at Lime Kiln
After an eventful quarter at sea collecting data we finally had the opportunity to analyze it and see our results. We presented posters at the Salish Sea Ecosystem Conference in Vancouver, Canada. We, the students, presented posters, talked with many scientists, and sat in on 3 days of presentations. We were all extremely blessed to have received this opportunity as it has helped in networking and giving us a glimpse in the scientific world. We will now all go our separate ways, but we will never forget the Beam Reach experience!
Sharon with poster at Salish Sea Ecosystem Conference
All the times we missed the orcas passing the Lime Kiln during our land-based research were about to be made up for…
Once we were aboard our catamaran home, our lives could basically revolve around the movement of the orcas, and it didn’t take long for that to begin. Since we started taking data on the whales right from day one, we had to take what we had learnt at the Lime Kiln and adapt quickly to data recording at sea.
“Permission to Deploy the Arrayâ€:
Once the whales were around us, we would deploy a four hydrophone array from the back of the boat and start recording. Laura listened to the calls and clicks being recorded in one minute time segments and recorded what she could hear on a phonation sheet so we could go back and listen to the best recordings afterwards. We also played the hydrophones through the speakers throughout the catamaran, so even those of us not working on the acoustics could have the full effect while we were with the whales.
The hydrophone array recording equipment (left) and the team preparing to record the whales on our first day (right).
Sharon and I were on behaviour lookout. The idea was to call out every whale we saw with a clock bearing, a distance, and what activity they were doing, while Hayley wrote all this information down on a behaviour sheet. We were also specifically recording surface active behaviours (such as tail slaps and breaches) and foraging behaviour for our own projects. Sounds simple enough, but when you have anywhere from 5 to 50 whales in sight, 360 degrees around the boat, things got pretty crazy (but crazy in the best way possible, this is what we were here for!).
An orca breaching (left) and J26 – “Mike” swimming past the Gato Verde (right) during our data collection.
Since Beam Reach 112 had some of the most orca encounters while out on the water, this routine was continuously practiced and fine tuned, but every so often there were days without orcas where we could experiences some other aspects of life at sea.
While the orcas are away:
One of our other main focuses while living at sea was learning about sailing. We had lessons beginning with all the basic parts of a sail boat, and progressing through raising the sails, choosing an appropriate sailing course, steering, tacking and jibing, and learning the right of way rules. It was great experience going through all the steps required in order to sail, and to help eachother learn along the way. We even had the opportunity to sail with some near gale-force gusts making it all the more exciting.
Preparing to raise the main sail
We also quite often had some other playful cetaceans visit us while the orcas were out at sea. Dall’s porpoises would bow-ride infront of us, most often near the Lime Kiln. We would lie on the front on the boat and watch them swimming just a couple feet below us. Some would even turn on their sides to get a better look at us and then come up to give us a splash, seemingly on purpose. We even thought we could hear them clicking on our “listening hydrophone” we had deployed one day as they approached our stationary boat.
Other research we conducted while the orcas were away included CTD casts, which took the whole team to lower the CTD (an instrument used to obtain a depth profile of temperature, salinity, and various other water measurements) 60 meters into the water, and then use a winch to crank it back onto the boat. I also fished for salmon and analyzed fish finder data from the boat for my project while the orcas we away, and had great success doing so!
The CTD in the water (left) and the crew waiting to haul it back up (right)
Salmon fishing off the boat (left) and a successful catch of a juvenile Chinook (right).
The whole Beam Reach crew was represented today in two killer whale sessions at the Salish Sea Ecosystem Conference. The sessions were convened by Scott and involved a great line-up of experts(see list of presenters below) talking about recent results from from non/invasive studies of southern resident killer whales (SRKWs).
Val gave a talk on underwater noise in the SRKW critical habitat and estimated that ships dominate the noise budget 83% of time (see plot at right). This works out to a long-term average of nearly a ship per hour!
Charla Basran with her poster
Jason gave a talk on compensation in ship noise. Andrea Buckman — one of our visiting experts this fall and last spring — spoke about the variable condition of chinook salmon. Robin, Laura, Sharon, Charla, and Hayley attended the sessions, and then continued to share and display their posters — now available on-line as PDFs — listed below.
Student posters:
108 – Sharon Bannick – Movement and Surface Active Behavior of SRKWs in Response to Current Velocity and Salinity
110 – Hayley Dorrance: Can clicks tell us anything about the foraging behavior of SRKWs?
112 – Laura Moe: Variations in S6, S10, and S19 calls in SRKWs
Session descriptions and speaker lists:
The killer whales of the Salish Sea are listed as threatened or endangered in both the U.S. and Canada. As the scientific and stewardship communities continue to weigh the costs and benefits of invasive methods like satellite tagging, there is a pressing need to exchange all available information from non-invasive research techniques. There are also renewed efforts on both sides of the border to integrate the management of killer whales and the listed species, like Chinook salmon, upon which they prey. 2011 has also brought Federal regulation of orca-boat interactions in the U.S. This session will survey recent scientific results, with an emphasis on less-invasive techniques and new implications for transboundary killer whale management.
4B: Science and management of killer whales I
John Ford
Pacific Biological Station, Fisheries and Oceans Canada
Contrasting long-term trends in occurrence and abundance of killer whale ecotypes in the Salish Sea
John Ford, Graeme M. Ellis, John W. Durban, Kenneth C. Balcomb
Amalis Riera
University of Victoria
Acoustic monitoring to delineate killer whale critical habitats off southwestern Vancouver Island
Amalis Riera, John K. Ford, John A. Hildebrand, Sean M. Wiggins, N. Ross Chapman
Samuel Wasser
Center for Conservation Biology
Non-invasive physiological monitoring of Southern Resident Killer Whales
Samuel Wasser, Katherine Ayres, Jessica Lundin
Peter Ross
Fisheries and Oceans Canada
Ranking contaminant threats to the killer whales of the Salish Sea
Peter Ross, John K.B. Ford, Andrea Buckman, Marie Noel, Frank A.P.C. Gobas, Steve Jeffries
Teresa Mongillo
Herrera Environmental Consultants, Inc.
Health implications of exposure to a mixture of pollutants in Southern Resident Killer Whales
Teresa Mongillo, Gina M. Ylitalo, Sandra M. O’Neill, Linda D. Rhodes, Dawn P. Noren, M. Bradley Hanson
Val Veirs
Beam Reach Marine Science and Sustainability School
Underwater noise in the critical habitat of the endangered Southern Resident Killer Whales
Val Veirs, Scott Veirs, Jason Wood
5B: Science and management of killer whales II
Rob Williams
Oceans Initiative
Inextricably linked: boats, noise, Chinook salmon and killer whale recovery in the northeast Pacific
Rob Williams, Erin Ashe, Christopher W. Clark, Philip S. Hammond, David Lusseau
Jason Wood
SMRU Ltd.
Shipping noise and vocal compensation by Southern Resident Killer Whales: Do some ships have a larger impact?
Jason Wood, Peggy Foreman, Val Veirs, Scott Veirs
Jeffrey Dismukes
Sysstat, Inc.
Quantification of average summer season marine vessel traffic in the San Juan Islands June 12 – September 7, 2010
Jeffrey Dismukes, Jonathan Riley, Greg Crenshaw
D.A. Giles
University of California, Davis. Dept. of Wildlife, Fisheries, Conservation Biology
Using non-invasive remote sensing equipment and GIS to assess potential effects of vessels on Southern Resident Killer Whales in the Salish Sea
D.A. Giles, Kari Koski, Rose Cendak, Nicholas Roseberg
Andrea Buckman
Department of Fisheries and Oceans
Variability in Chinook salmon condition and implications for resident killer whales
Andrea H. Buckman, Nik Veldhoen, Caren C. Helbing, Kristi Miller, John K.B. Ford, Peter S. Ross
Lance Barrett-Lennard
Vancouver Aquarium Marine Science Centre
Saving salmon for endangered killer whales: A new paradigm in wildlife management?
Larry Rutter
NOAA Fisheries, National Marine Fisheries ServiceA scientific workshop process to evaluate the effects of salmon fisheries on killer whales
Associated posters:
Associated posters:
107 – Characterizing boater interactions with SRKWs in their critical habitat
111 – Soundwatch recommendations for special management areas for KWs
113 – Responding to the threat of oils spills to SRKWs
Thanks to the PRR Facilitator, Kirsten Hauge, for her help facilitating the sessions by keeping time for the speakers. And thanks to Larry Rutter of NOAA/NMFS for calmly reading his talk from his hard-copy notes because Scott had misplaced his presentation!
Stand by for notes from other sessions, recordings, more blog posts, etc. from the conference…
Learning about the ecosystem an organism belongs to is often just as important as learning about the organism itself, so that’s what Beam Reach 112 set out to do for the first few weeks on land. We were fortunate enough to be able to set up our land based research at the Lime Kiln lighthouse where the orcas are seen frequently (usually!). Though the orcas managed to elude us the majority of the time we were at the lighthouse, we had no shortage of research we could do.
Marine Mammal and Bird Observing:
Each day at the lighthouse, one person was on observation. For 45 minutes at a time, every bird and mammal spotted was recorded. Seagulls, Cormorants, Murres, Dall’s porpoises, Harbour porpoises, and playful seals were regulars at the lighthouse on pretty much a daily basis.
Harbour porpoise and a peeking seal observed from the platform infront of the Lime Kiln lighthouse.
Underwater Camera Monitoring:
An underwater splashcam was installed directly infront of the lighthouse with the first hydrophone and the, also newly installed, CPODs (for detecting dolphin and porpoise clicks) in view. One person’s duty was to record everything that swam infront of the splashcam on paper and as 10 minute video recordings. We often had kelp greenlings and rockfish hanging around in view, taking the occasional nap ontop of the CPODs, or swimming up to give the camera a big kiss. We also got footage of the occasional large lingcod, seals swimming past, and schools of salmon swimming north (headed for the Fraser River?).
Using a YSI monitor, two people recorded water temperature, salinity, and dissolved oxygen daily. Then they also took a plankton tow and attempted to identify as many species as possible. The average water temperature was 10.85°C, average salinity was 28.95ppt, and average dissolved oxygen was 6.25mg/L. Some of the most commonly identified plankton species were Chaetoceros, Cylindrotheca, and Skeletonema.
Chaetoceros (left) and Skeletonema (right) found in samples collected at the Lime Kiln lighthouse.
Orcas!
When we finally caught the orcas swimming past the lighthouse, we were ready to spring into action. One person started recording and monitoring the hydrophones. Audible calls and clicks were recorded on a phonation sheet so that we could go back and listen to the best times of the audio recordings. The other three of us headed down to the “iron post†infront of the
lighthouse, armed with a behaviour sheet, binoculars, and the camera. The goal was to record clock orientation (to the iron post), travel direction, distance, and any surface active behaviours, and attempt to get as many identification pictures as possible. This information goes into the Beam Reach archives to help with future projects, and can be used to help us confirm localizions of calls from the hydrophone recordings.
Orcas passing by the Lime Kiln lighthouse on September 15, 2011
Our time at the Lime Kiln helped us learn about the “big picture” of all the pieces of the orcas’ environment. Though it was kind of hectic (yet extremely exciting) when we did get to record orca data, it gave us a good introduction to what life on the Gato Verde would be like…
Through Beam Reach’s Sustainability portion of the program, we (the students) get to choose projects to either educate the public or volunteer our time. One of the projects we all agreed on and decided we must do is volunteer for SoundWatch. SoundWatch is the boat that follows the orcas around and educates the public about the laws pertaining to them.
David scoping for whales
All four of us got our own day to volunteer for SoundWatch. I was the third one to go, and I was ecstatic because I had never experienced the orcas from a boat yet! A man named David Howitt picked me up, and we drove to the other side of the Island to Snug Harbor to meet Tyler, another volunteer. After getting my paperwork all squared away, I hopped in the boat with my mustang suite on (these huge orange suites that are very warm PFDs) and we went down to Eagle Point (south of the lighthouse) and found the orcas right away! It was incredibly calm. I was amazed at the amount of fishing boats that were out; I counted 60 from where we were at, and the orcas were right in the middle of them. It was insane! Right away it would’ve already been crazy to try to coax the boaters away from the pod’s path, so we just made sure everyone was stopped so that the orcas could go through. Thankfully they made it out of that mob of vessels safely. Wow, just hearing them breath all around you is breathtaking. It was incredible being out there.
Every half hour it was my job to record where we were (latitude and longitude), how many boats (and types of boats) were present, what the whale’s behavior was, and which pods we were following. Weather was also noted. I was also in charge of giving people a copy of the regulations with this long stick with a little clip. We were lucky, everyone was grateful that we were out there, and treated us well. I guess that doesn’t always happen.
Near the end of the day the whales moved further west, the crowd of boats surrounding them died down. I saw some bull kelp in the water and I thought “I want to try playing one of those…†I’d heard of people being able to play bull kelp, and some even do it to summon the orcas. I’m a music minor, so the idea was hard to pass up! David let me stop for some bull kelp and he cut the end off and made it into a horn! Bull kelp is a long hollow tube that slowly narrows as it gets longer, and it was surprisingly slimy! First David had a go, and being a past horn player himself, I would believe that he could summon the orcas with that sound. Then he let me try, and now I can honestly say I played kelp! Like any brass instrument, I could get a few notes out of the one piece of kelp, and we’d cut it to different sizes to get different sounds.
Not long after that there were only about 3 boats left out there. We did our count, and said goodbye to our black and white friends and called it a day.
Beam Reach is a program that provides extensive learning opportunities and self discovery for every participating individual. Each person has their own personal experience, however different from another, and helps to broaden minds and mold a more rounded individual. Among the many educational opportunities students were educated in sailing around Haro Strait was one of the most enjoyable. The captain of the beautiful Gato Verde, Todd Shuster taught us the in’s and out’s of sailing. To understand how “easy†Beam Reachers had it with only 3 sails (screecher, jib, and main sail) we watched an educational video on sailing “Around Cape Horn†made and narrated by Irving Johnson, which inspired the following video. Once the basics were taught we put our knowledge to the test…
42' catamaran - Gato Verde
On October 10, 2011 each student had a round at being the helmsperson at the Gato Verde. The helmsperson practiced calling jibes and crashing through the stormy waters off the coast of Kellett Bluff. Students not driving the catamaran had to focus their concentration on helping the boat jibe. One student on port and another on starboard when the helmsperson yelled “READY TO JIBE?†they respond “READYâ€. The helmsperson, knowing the students were ready yelled “JIBING†and one student would release the jib sheet while the other would pull in the slack on the opposite side of the catamaran. After jibing the Gato the working crew got to relax and enjoy the experience of sailing around “Cape Kellett Bluffâ€. It was safe to say the 30 knot wind gusts made for an eventful and wet sailing experience. Although the crew was chilled and soaked to the bone, the cargo did arrive safe and dry into Garrison Bay!
My first reaction to the Gato Verde was, “Wow. It’s roomy!†We have it really nice on this French vessel. It was built in 1998 and Captain Todd said the model type hadn’t changed much since it was built, and it felt clean and new. I first looked around the boat, and there are 4 double cabins, and 2 single cabins up in front. The four of us have two double cabins on one of the catamaran’s hulls. The doors are made out of a type of red wood, and the accommodations feel almost hotel-like compared to what I was expecting! My roommate and I share a bed, and again I was amazed at the amount of space we had. I initially imagined being smashed together in a twin size cot. I guess my imagination goes a bit far when they said we’d have tight accommodations! In the middle of the two hulls is the actual cabin, where the kitchen/living room is which consists of a round table with booth-like chairs that also act as storage for our food (that we got the luxury of picking out ourselves instead of going through NOLS). This was our spot during the evenings of entering data that we had gotten throughout the day, or paying catch-up from previous days! After hauling stuff onto the boat, we were off! As we were going to our port, we just explored the boat, and went outside on the “trampoline†which was a mesh that you could sit on and really feel like you were as close to the ocean as you could possibly be without jumping in!
Blackberry!
The very first full day on the boat we got to encounter the whales by salmon bank! So we headed out straight away to go catch them We learned on the fly as we set in the hydrophones and scrambled for data sheets that we’d printed off for our specific projects. It was so amazing: I heard their calls as I heard them come up breathing all around us. Sound travels so brilliantly across the water, you can hear them breathe from pretty far away and still feel like they’re so close. My job was to sit with headphones on until they made calls or clicked and note when it happened, and what type of call it was. The sun was WARM on my back; another luxury I hadn’t planned on having while I was on the boat. We collected data for over three hours! And it felt like 30 minutes. We turned in to Snug Harbor and started looking at the photos at the end of the day. Both Charla and I made the same conclusion: we saw J16 (Slick) and J27 (Blackberry)!
Slick!
We saw whales every day for the first three days of our trip, still learning how to do things on the go. Our first non-whale day was Charla’s birthday, the 23rd, and as close as the trampoline gets you to the water, we decided it wasn’t enough. After a CTD cast, Charla announced, “Okay, we’re jumpin in!” What peer pressure! I can’t say no to such a simple birthday wish, despite my horror to the cold rush that was about to come. But it was such a beautiful warm day! We threw our suits on and it was actually really comfortable out in the sun. And we jumped in! Into 700 feet of water. I felt so small. We swam underneath the Gato, and it was actually quite refreshing after not showering for 5 days.
We were locked into Snug Harbor for the majority of the next day due to fog, but when we finally got out, the most incredible thing happened: for the first time of the trip, we got to experience dall’s porpoises riding our bow! We all laid on our bellies at the end of the trampoline and looked over the bow; if I wanted to, I felt like I could reach down and run my hand across one. You could tell that they were just as curious about us as we were about them, because every so often they’d lean far over on their sides and take a look at us. It was a pleasant end to a relatively uneventful day.
The next couple of days, instead of being trapped by fog, we were trapped by 40 knot winds. We had sailing lessons during this time from Captain Todd (just white-board stuff of course). In the afternoon, we heard the whales were right outside the harbor, and we declared that the wind died down well enough for us to go out and take a peak! For the first time of the trip, all of my rain gear went on and we got to enjoy the whales for about a half hour. I couldn’t deploy the hydrophones unfortunately, because the waves were too high. We went to Garrison Bay for a while because it’s more sheltered than Snug for the winds that weren’t predicted to let up any time soon.
The next day, as predicted, we had 40-knot winds again, and we experienced it right in the harbor! Whales were right in Haro Straight next to us, but we were stuck. By the evening we all went to land and walked for a while at English Camp for some much needed exercise! We also watched Robin’s favorite movie in the world: Life Aquatic.
The next couple of days were data days! We ended up being able to catch the whales right away in the morning! It was great getting back into the groove after a few storm days of storm. I guess we’re really lucky, EVERY day that we’ve had good weather we’ve been able to be with the whales for a while! I think I got some amazing recordings from L pod today, and we’ve been seeing mostly J’s and K’s throughout the week, so this was really exciting for me! I felt like it was like a one-time deal, and the adrenaline kicked in. Such precious data! It was a perfect closing to our first cruise. The final day I went on Soundwatch with Sharon before going back to the labs. Seven Days out of the eleven we got to be with our black and white friends, and I never felt so lucky.Â
Throughout my life I’ve always seen a balance with everything. Too much of one thing is not ideal, but not having enough is not ideal either. I was looking for papers to blog about fish sustainability in our oceans, and I found an article that stated right in the abstract that there are two sides to the issue. One side sees universal failure in fisheries management and wants to use protected marine sanctuaries as the ultimate tool to try to rebuild the state of the marine ecosystems around world. This has been done in various locations around the united states with many positive results.
On the other side of the issue are people who are working in fish industries who realize that there have been numerous failures in the management of ocean fishing. But there have also been success stories, and instead of simply making sanctuaries, “This group argues that we need to apply the lessons from the successful fisheries to stop the decline and rebuild those fisheries threatened by excess fishing.â€
Worm et al. stated that if fish stocks keep declining in the same rate as they are now that the world fish stocks will collapse by 2048. With collapsed stocks, diversity of an ecosystem shatters. Worm et al. proposed that the health of a habitat is directly reliant on the diversity that it holds. They set up 32 controlled experiments as well as 12 estuarine experiments to examine the effects of variation of marine diversity of fauna and flora, resource use, and nutrient cycling. They found that increased diversity enhanced all ecosystem processes.
Worm et al. The graphs of Marine biodiversity and ecosystem functioning in controlled experiments.
He found that the more diversity an environment contained, the more capable it was to withstand stress; a factor quite important in these environmentally stressful times.
A proposed explanation was given to explain the advanced recovery at high diverstiy: fishers can switch more readily among target species, and therefore providing overfished species a chance to recover. By restoring biodiversity in the marine habitats through sustainable fisheries, pollution control, and the creation of marine reserves (as stated above), we can reliably invest in what our oceans provide us.
Annoyingly so, I love seafood. When you become a marine biology major, you realize how far we are away from having sustainable fisheries, and it can be quite disgruntling to discover that what you love to eat is not a sustainable food source. But now I carry a seafood watch card in my purse that was released through the Monterey Bay Aquarium.
This being said, it is vital for our endangered southern resident killer whales that we do the above suggestions: create marine sanctuaries and create regulations of fishing to maintain diversity and the ecosystem’s ability to handle stress from a rapidly altering environment. There has always been a sense of “freedom of the sea†and the idea of regulations on fish stocks is relatively new. But due to our intense fishing practices, regulations must be installed if we or other creatures depending on fish such as killer whales want to able to fish in the future, especially for the threatened King salmon.
Fish hatcheries have become ever more important in recent years due to the declines in wild stocks. The aim of hatcheries is to replenish the wild stock in order to keep the fishing industry sustainable, but there is still debate as to what is the best approach to this without causing further damage to the wild population. In an attempt to make improvements to hatchery practices, Hitoshi Araki studied the reproductive success of hatchery trout compared to wild trout, and made suggestions in his paper Hatchery Stocking for Restoring Wild Populations: A Genetic Evaluation of the reproductive Success of Hatchery Fish vs. Wild Fish (2008).
The hypothesis was that fish bred using the traditional hatchery methods, in which the fish are usually non-local and are bred for many generations in captivity, have much lower reproductive success than both supplemental hatchery fish and wild fish. The idea behind supplemental hatchery methods is to use local parent fish to breed “wild stock” hatchery fish in a protected environment, and then release them into the wild population, with the overall goal being to re-create a sustainable wild population. Using DNA analysis of steelhead trout from the Hood River, Araki determined the reproductive success of traditional hatchery fish, supplemental hatchery fish, and wild fish. He found that the more generations bred in a hatchery, the less reproductively successful the fish are.
Picture 1: Araki used his own data and data from previous studies to show the decline in relative reproductive success (RRS) as the number of generations in a hatchery increased.
Araki also found that supplemental hatchery fish had significantly higher reproductive success than the traditional hatchery fish, though they still had lower reproductive success than the wild population. When a wild stock parent was crossed with a traditional hatchery parent the reproductive success dropped. This shows the effect that hatchery fish can have on the wild population. If traditional hatchery fish continue to be released into wild populations in attempt to sustain them, they will continue to lower the reproductive success of the wild population.
It seems that, though hatcheries have a positive sustainability goal in mind, the traditional methods they are using to replenish wild stocks are somewhat counter-acting what they are trying to achieve. Though it may be more work to implement supplemental hatchery methods, the benefit of higher reproductive success of the population should be worth it.
Araki used steelhead trout as his example organism, but it is assumed that similar principles could apply to other fish species. In the San Juan and Vancouver Island area, salmon hatcheries are an important part of the fishing industry (and produce important food for the Southern resident orcas!). Since Chinook salmon are endangered in the area, a large amount of juveniles are released into the wild from hatcheries. From the information I could find, it seemed hatcheries in the area are attempting to use methods closer to supplemental techniques rather than the traditional methods. For example, the San Juan Enhancement Society in Port Renfrew, BC collect their broodstock (parent fish) of Chinook from a lake connecting to the San Juan River, therefore the juvenile fish are being released into their natural habitat. Though it isn’t stated how many generations are produced in the hatchery, it still could be considered a step in the right direction compared to using a non-local broodstock. Hopefully in the future hatcheries move towards supplemental practices so that the wild stocks, the ecosystem, and everyone utilising the fish can further benefit from sustainable fish populations.
Picture 2: Both wild and hatchery juvenile Chinook can be found in the San Juan Islands, as our Beam Reach class found out while beach seining on Lopez Island. The hatchery salmon had their fins clipped for identification.
Concerns about overfishing are a pressing issue. Technological advances, have made fishing industries much more efficient. Fish are caught at greater depths, and in much larger numbers. Some scientists have estimated that as much as 90% of large predatory fish including sharks, swordfish, and cod have been removed from the oceans of the world . With so many large predatory fish having been removed from the ocean it may seem that there are plenty of other fish in the sea, however this is untrue for a growing number of fish populations. Other factors, including pollution, fishing methods, and habitat destruction contribute to the decline of many fish populations, including Chinook salmon.
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