Fish Archives - Page 2 of 2 - Seattle Aquarium

Expert care for hundreds of species and thousands of animals

Posted on September 7, 2021February 9, 2024 by Emma Leiser

The Seattle Aquarium is home to nearly 400 species and over 12,000 individual mammals, birds fish and invertebrates. And, just like humans, these species have their own distinct care needs that change as they age. “All animals at the Aquarium have care plans that are customized to their species and the needs of the individuals or groups,” says Senior Veterinarian Dr. Caitlin Hadfield, MA VetMB DAZCM DECZM.

Being responsible for so many species and individuals means that animal care at the Seattle Aquarium is a team effort. Our veterinary and husbandry staff monitor the health of the animals every day and work together to provide the best life possible for them. “That’s the essence of good animal welfare,” notes Dr. Hadfield.

What’s it like being the doctor in charge for so many mammals, birds, fish and invertebrates? “It’s a mixture of routine preventative care—like wellness exams and environmental quality assessments—and reactive care, where we respond to changes we’ve seen in the animals or their environment,” says Dr. Hadfield. “With so many animals, we rely heavily on our professional staff and animal records to identify anything of concern, then work together to understand the situation and identify the best solution if needed. Because of the variety of species, I often reach out to colleagues with different fields of expertise so that, together, we can provide a great quality of care.”

Long (long!) lives

Here’s a fast fact: The average life span of a male Pacific harbor seal (Phoca vitulina vitulina) in the wild is 26 years¹. Longtime Seattle Aquarium favorite Barney is now 36 years old, well above the average in the wild population. “Like any elderly animal, including us humans, he has some health issues, but is enjoying life,” says Dr. Hadfield.

Barney is just one example of how animals in human care at zoos and aquariums accredited by the Association of Zoos & Aquariums (AZA), including the Seattle Aquarium, tend to live significantly longer lives than those in the wild. “Over the Aquarium’s history, lessons learned and the application of new, innovative technologies designed for animal care have enabled our team to provide a good quality of life well beyond the expected life span for their counterparts in the wild,” notes Director of Life Sciences Grant Abel.

Speaking of Barney…where did he come from?

Visitors often ask about the origins of the Aquarium’s birds and mammals (and not in the “birds and bees” way!). Barney was born right here, in 1985—as was sea otter Aniak, in 2002. In fact, every marine mammal and bird in our care was either born in a zoo or aquarium, like Barney and Aniak, or rescued and deemed non-releasable by the U.S. Fish and Wildlife Service or the National Marine Fisheries Service, like sea otters Adaa and Mishka. Rescued animals that are deemed non-releasable either have a health issue or stranded too young to be able to survive in the wild.

Stay tuned for our upcoming blog posts for details about how we care for aging animals, as well as the AZA species survival plans for maintaining healthy, genetically diverse populations of animals within accredited zoos and aquariums.

Lastly, another fast fact: The Seattle Aquarium was first accredited by the AZA in 1979 and, like all accredited members, is subject to a thorough on-site inspection every five years to renew that accreditation.

¹ https://animaldiversity.org/accounts/Phoca_vitulina/#A79C1289-12A8-441B-8408-D30C2A18F1BE

Specialist surgeon visits Aquarium to help a red Irish lord

Posted on July 6, 2021May 9, 2024 by Emma Leiser

An egg-bound red Irish lord (Hemilepidotus hemilepidotus) at the Seattle Aquarium needed surgery, so a board-certified surgeon from Animal Surgical and Orthopedic Clinic (ASOC) performed the necessary procedure. Senior Veterinarian Dr. Caitlin Hadfield and Curator of Fish & Invertebrates Tim Carpenter here at the Aquarium explain more:

Q: What can you tell us about this species?

Tim: Red Irish lords are part of the sculpin family. They tend to rest on the bottom of shallow waters, down to depths of 1,500 feet. They’re common from the Bering Sea, near Alaska, to Washington, and are rarer south to central California. These fish are highly camouflaged and often overlooked by divers. Given that this species is not a common commercial or recreational fishing target, complete biological data on the species is not well-published. Based on limited fishing and other data gathered by the state of Washington, they can grow up to 20 inches long and 2.45 pounds in weight. Their maximum age is at least 6 years old.

Q: What does it mean for a fish to be egg bound?

Tim: Egg binding occurs when a female produces eggs but is not able to release them. This can lead to a buildup of eggs with each successive “clutch”, and the eggs become increasingly abnormal over time. There are many possible causes; we’re not sure why this species gets egg bound.

Q: Why was a board-certified surgeon needed to assist on a surgery for this red Irish lord fish’s case?

Dr. Hadfield: Aquarium and zoo veterinarians frequently reach out to specialists when we think it’s in an animal’s best interest. In this case, the anatomy is the main reason.

In fish like koi and salmon, the ovaries are two separate structures that sit loosely within a thin membrane and are easy to remove if they cause issues. In Irish lords, the two ovaries combine at the back, making them U-shaped, and that caudal aspect (i.e., near the tail) is tightly adhered to the body wall and the colon. Combined with that, these abnormal ovaries are very large—about 50% of the fish’s body weight—and the ovarian wall holding in all the little eggs is fragile.

These factors make this a particularly difficult surgery. We had tried environmental changes and hormones to induce egg laying but without success, and this surgery was needed to save the fish’s life. Dr. Alex Aguila, a board-certified surgeon from ASOC, and his surgical assistant, Sarah Gagliano, have extensive experience with difficult surgeries.

Alex was able to remove all the ovarian tissue, which is great news. The surgery is challenging and it is common to have to leave some of the ovarian tissue; this can regrow and cause more issues later on. Dr Aguila was also fast! This meant we were able to reduce the total anesthetic time to about 90 minutes, which also helps improve the long-term prognosis for the fish. And this was also a great opportunity for us all to work together and learn. The Seattle Aquarium has worked with ASOC for over 30 years, and we look forward to continuing our strong relationship well into the future.

Q: How does surgery happen on a fish?

Dr. Hadfield: To anesthetize a fish like this, we use a drug that is dissolved in the water. We keep that medicated water flowing over the fish’s gills through the surgery using a pump that moves the water through a big loop while we monitor the condition of the water. This lets us keep the fish’s belly out of water for the surgery. We also provide pain relief, similar to what you or your pet would receive, including anti-inflammatories, opioids, and local anesthesia around the surgery site. Once the fish is pre-medicated and on our surgical system, the surgeon can drape the site and get started. While there are differences in anatomy (like a lack of fur!), how surgery is done is similar to dogs and cats, including using the same types of sutures (stitches) to close up the body wall and skin.

Q: What happens next for the care of this red Irish lord?

Dr. Hadfield: The surgery was about a month ago, and the fish is doing great. She is eating again and looking like a healthy red Irish lord. She will get some more recheck exams and then move back to the Window on Washington Waters habitat. She has a small transponder now (just like your dog or cat), so we will be able to monitor her over time to see how she does.

Q: What are other examples of when specialists visit the Aquarium to help the animals in our care?

Dr. Hadfield: We are lucky enough to have a large support network of specialists in the zoo and aquarium field as well as in the private sector, including anesthesiologists, cardiologists, radiologists, ophthalmologists, and oncologists (lots of -ologists, really!). These specialists routinely donate their time and expertise to help improve the health and welfare of the animals under our care. One of the things that I appreciate most about this field is that we all want to learn and help each other out.

Q: When has the Aquarium shared our expertise in the community or with peer institutions and other organizations or efforts?

Dr. Hadfield: This is a hugely collaborative field, and we each try to help where we can. People often reach out to us to discuss challenges they may be having with species that we have under our care, as well as programs that we are particularly well known for, such as our animal welfare assessments and conservation programs.

You can come check out our Tropical Pacific habitat and try to find a red Irish lord during your next visit to the Aquarium. Be sure to book your ticket in advance; we look forward to seeing you!

Climate resilience in coral reef fish communities

Posted on June 9, 2021February 9, 2024 by Emma Leiser

Fish assemblage structure before and after a marine heatwave in West Hawaiʻi

Guest blogger Amy Olsen began her time at the Seattle Aquarium as a volunteer diver in the Underwater Dome habitat. She is now a laboratory specialist/research technician in the Conservation Programs and Partnerships department. Her Master in Marine Affairs program is in the School of Marine and Environmental Affairs at the University of Washington.

Coral reefs are subject to marine heatwaves caused by human-induced climate change. Long-term thermal stress can negatively affect corals and the associated marine organisms that use these areas as critical habitat by causing coral bleaching. Coral reefs provide important ecosystem goods and services such as fisheries and tourism as well as aesthetic and cultural value. Healthy coral reefs have been estimated to add $477 million annually to Hawaiʻi’s economy through tourism and subsistence, recreational and commercial fisheries (Cesar & van Beukering, 2004).

For my master’s thesis project, I examined coral reef resilience to climate change by analyzing changes in fish assemblages (i.e., which species exist in the same area at the same time) after a marine heatwave. I analyzed 11 years of subtidal video survey data in three areas in West Hawaiʻi, capturing a marine heatwave event from 2014 to 2016. Fish were counted and identified to species, then assigned to one of seven functional groups: predators, secondary consumers, planktivores, corallivores and three herbivore groups—scrapers, grazers and browsers.

The dataset I used was collected by my supervisor, Dr. Shawn Larson, curator of conservation research at the Seattle Aquarium. This work falls under climate resilience, one of our three organization-wide conservation priorities along with sustainable seas and clean waters.

The Seattle Aquarium has been conducting video-based reef monitoring surveys every year in Hawaiʻi since 2009. The goals of this monitoring project are the following:

Document changes in fish diversity and abundance over time.
Determine coral cover (how much of the ocean bottom is covered by coral versus rock or sand), identify coral species and calculate percentage of coral bleaching over time.
Collect environmental data such as bacteria, nutrients and microplastics.

I used statistical tests to evaluate how the fish communities changed after the marine heatwave. All three areas in West Hawaiʻi were found to be different in the years after the heatwave. Interestingly, regardless of how differently these areas are managed or how different the habitat is, all three communities became more similar to each other.

This has been previously described in the literature where climate changes in the marine environment favor small, generalist, algae-eating fish that are able to adapt to these changes. This is called biotic homogenization and has been cited as a pressing global biodiversity crisis (Dornelas et al., 2014, Magurran et al., 2015, McGill et al., 2015).

Kona, the Marine Life Conservation District with the highest level of fishing protection among our sites, showed the highest total fish abundance and least variation over time in abundance over the study period, suggesting ecosystem stability. These sites had the highest diversity values and also documented the highest coral loss. While the fish assemblage was significantly different after the marine heatwave, the observation that fish abundance remained high could indicate this area has higher resilience than the other two areas, and may suggest more stability to new or unusual environmental conditions (Bernhardt & Leslie 2013).

Marine protected areas can be an effective management strategy to prevent overfishing, protect diverse species and provide a refuge for life stages that are more sensitive, but they do not prevent warming of the ocean surface or coral bleaching. However, management policies that prevent overfishing of herbivorous fish, such as browsers or scrapers, can prevent phase shifts from healthy coral reef systems to algal-dominated systems which has been found to aid reef resilience (Hughes et al., 2003).

Protected reefs lead to higher abundance and biodiversity of reef fish (McLean et al., 2019). Coral and fish species responses to thermal stress is highly variable, so networks of marine protected areas require thoughtful place-based approaches for effective implementation. Success is dependent on an effective combination of science-based management, public support and political will (Bellwood et al., 2004).

Understanding how marine heatwaves impact coral reef communities can guide decision-making for effective coastal management. Continued long-term monitoring is necessary to evaluate disturbance impacts on the coral reef ecosystem, as we anticipate climate change and marine heatwaves will continue into the future.

Take action!

To help protect coral reefs from these stressors, the Seattle Aquarium is supporting policies such as the Restoring Resilient Reefs Act (S.46 and H.R.160). This act would provide new federal grants to support state coral reef management and restoration and respond to coral reef emergencies and disasters. You can help! Visit this Aquarium Conservation Partnership quick action page to encourage your members of Congress to co-sponsor this bipartisan legislation.

References:

Bellwood DR, Hughes TP, Folke C, Nyström M (2004) Confronting the coral reef crisis. Nature 429:827–833.

Cesar HSJ, van Beukering PJH (2004) Economic valuation of the coral reefs of Hawaiʻi. Pacific Sci 58:231–242.

Dornelas M, Gotelli NJ, McGill B, Shimadzu H, Moyes F, Sievers C, Magurran AE (2014) Assemblage time series reveal biodiversity change but not systematic loss. Science (80- ) 344:296–299.

Hughes T, Jackson J, Kleypas J, Lough J, Marshall P, Palumbi S, Pandolfi J, Rosen B, Roughgarden J (2003) Climate Change, Human Impacts, and the Resilience of Coral Reefs. Science (80- ) 301:929–933.

Magurran AE, Dornelas M, Moyes F, Gotelli NJ, McGill B (2015) Rapid biotic homogenization of marine fish assemblages. Nat Commun 6:2–6.

McGill BJ, Dornelas M, Gotelli NJ, Magurran AE (2015) Fifteen forms of biodiversity trend in the anthropocene. Trends Ecol Evol 30:104–113.

McLean M, Auber A, Graham NAJ, Houk P, Villéger S, Violle C, Thuiller W, Wilson SK, Mouillot D (2019) Trait structure and redundancy determine sensitivity to disturbance in marine fish communities. Glob Chang Biol 25:3424–3437.

Reducing oil spill risk to protect otters, orcas and more

Posted on May 5, 2021February 9, 2024 by Emma Leiser

Fossil fuels pose a huge risk to the health of our oceans. When we burn fossil fuels such as oil, coal and natural gas, more carbon dioxide goes into the atmosphere. As the ocean absorbs some of these emissions, the chemistry of the seawater changes. Ocean waters that are more acidic dissolve shells and coral skeletons and make it hard for animals to form new shells. These changes, along with ocean warming and other climate change impacts, harm marine ecosystems and the people who rely on them for their food, livelihoods and well-being.

The transportation of fossil fuels and the accompanying potential for oil spills threaten the waters of the Salish Sea every day. There are proposed projects that would further increase oil handling in Washington state, along with the chance of devastating oil spills from trains, tankers and barges. In a 2019 count by Friends of the San Juans, there were 25 proposed new, expanding or recently completed terminal and refinery projects, which would add 4,232 more vessel transits every year to and from ports in Washington state and British Columbia.

Some types of oil are light and float on saltwater, spreading out very rapidly and making the oil easily accessible to seabirds and mammals at the water’s surface. Other kinds of oils are heavy and sink, causing problems for fish and organisms on the seafloor. Animals are hurt when they inhale oil as they surface to breathe or swallow oil as they try to clean themselves. When birds’ feathers or mammals’ fur get coated in oil, it also undermines their insulation, making it difficult for them to maintain the right body temperature. Oil and gas transport in marine waterways is listed among the primary threats to the sea otter population. And it is estimated that an oil spill of 2,000,000–4,000,000 gallons may kill up to half of the remaining endangered southern resident orcas (1).

Many Seattle Aquarium staff have the federal and local training required to safely handle and care for wild marine animals in the event of an oil spill. Three of our staff are also trainers and provide annual Hazardous Waste Operations and Emergency Response (HAZWOPER-24) classes in the region with a focus on oiled wildlife response.

But we must do more than prepare for the eventuality of a catastrophic oil spill in the Salish Sea. Fossil fuels must be phased out to protect the health of our ocean and the marine species that call it home. The Seattle Aquarium has begun engaging with partners in the Stand Up to Oil coalition, a group of organizations committed to protecting Pacific Northwest communities from the health, safety and environmental threats of oil infrastructure and transport.

Over the last few months, we have raised our voice to oppose new fossil fuel infrastructure in Washington state and ensure that oil spill risks to endangered species are explicitly considered in project-approval processes. These efforts have included:

Opposing the Kalama methanol refinery: We joined many other organizations and communities in urging the Washington Department of Ecology to deny a proposal to build and operate a methanol refinery along the Columbia River in Kalama, Washington. The project would have resulted in significant greenhouse gas emissions for the next 40 years at all points in the process—from fracking and piping the gas to its conversion to liquid methanol and then to plastics or fuel, and then the burning of that fuel. In a huge win for the health of our ocean and climate, the Department of Ecology rejected this proposal in January 2021.
Ensuring better planning for oil spill risk: We have asked the Department of Ecology to require updates to oil spill contingency plans to better reduce the risk of oil spills to the endangered orcas.
Expressing concerns about oil terminal expansion: There is a proposal to expand the SeaPort Sound bulk oil terminal. We asked the City of Tacoma to closely examine potential harm to the sensitive intertidal and marine ecosystems of the Salish Sea.
Preparing for new rules for fossil fuels: This summer, the Washington Department of Ecology will develop rules for evaluating any new fossil fuel project proposals. This is an opportunity to ensure the Department of Ecology applies the best available science and social equity considerations in future permitting decisions. Be on the lookout for an upcoming action alert to help hold coal, oil and gas projects accountable for the air pollution they create.

We invite you to join the Seattle Aquarium in speaking up for the health of our ocean and climate! Get breaking news and urgent action alerts by subscribing to our policy email list.

(1) Lacy, R.C., Williams, R., Ashe, E. et al. Evaluating anthropogenic threats to endangered killer whales to inform effective recovery plans. Sci Rep 7, 14119 (2017).

Protect Bristol Bay

Posted on July 31, 2020December 19, 2023 by Emma Leiser

Last Friday, the U.S. Army Corps of Engineers cleared the way for permitting a huge mine at the headwaters of two major rivers that feed into Bristol Bay, Alaska—home to the world’s largest sockeye salmon fishery and one of the most prolific Chinook salmon runs.

The Canadian-owned Pebble Limited Partnership (“Pebble”) would extract gold, copper and molybdenum—materials of extremely high value, found in everyday items such as seatbelts, cell phones and electrical wires—through a new open pit mine.

The Seattle Aquarium strongly opposes the Bristol Bay Pebble Mine. Healthy oceans, fishing and Indigenous communities and local economies depend on wild and clean rivers and waterways. These will all be harmed if the Pebble Mine is developed. The science clearly shows the dangers posed by developing the mine are too great to allow the project to proceed. And yet, the Trump Administration is determined to do so, as it continues its relentless efforts to roll back environmental projections—from the National Environmental Policy Act to the Endangered Species Act—and ignores the call for environmental justice.

In the final environmental impact statement released last week, the Corps concluded that the mine “would not be expected to have a measurable effect on fish numbers” or “result in long-term changes to the health of the commercial fisheries.”

The science does not back up that finding. Mining in these rivers would cause both environmental and economic damage. The EPA’s earlier scientific assessment found that the mining activities would destroy more than 80 miles of streams and 3,500 acres of wetlands and generate billions of gallons of mine pollution. The surrounding marine ecosystem, $1.5 billion-dollar fishing industry, and over 14,000 jobs—including jobs held by fishermen from Washington state—that depend on these fish would be put in jeopardy.

We stand with Alaska Natives, fishing communities and others who have been opposing this mine for years. The salmon runs in Bristol Bay are essential to the health of the surrounding ecosystems and sustainable economies. We call on the EPA to follow the best available science and the principles of environmental justice and invoke a veto under Section 404(c) of the Clean Water Act.

If you’d like to take action, consider contacting your elected official and asking them to speak out against the Pebble Mine. Here in Washington, Senator Cantwell and Representative Kilmer have already done so—so please thank them if you are their constituent! You can also post your concerns on social media and tag @EPA and @USACEHQ.

Recovering Northwest salmon

Posted on April 7, 2020February 9, 2024 by Emma Leiser

We simply can’t have a week of online engagement about Puget Sound fish without devoting some very special attention to one of the most culturally significant and iconic local species, critical to the overall health of our Pacific Northwest marine and terrestrial ecosystems: the salmon.

Many people know that the broad term “salmon” encompasses several different species. Seven of those are found here in the Pacific Northwest: Chinook (also known as king), coho, chum, pink, sockeye, steelhead and cutthroat. And, within our Pacific salmon and Pacific trout species in Washington state are a whopping 486 distinct populations—each one a scientifically designated, biologically distinct group of individuals (e.g., Snake River spring/summer Chinook; Skagit River coho) adapted to specific streams, estuaries and other conditions.

When people join us for the Cedar River Salmon Journey each October to see salmon spawn, they’re witnessing the journey of a specific group of salmon, through specific conditions that only the Cedar River provides. Because of varying conditions from river to river and from the river mouth to the headwaters, each salmon population has slightly different timing for their reproduction: when they’re in the open ocean and signaled to return, when they start to move upriver, and when their eggs hatch.

Salmon start their lives as juveniles in local streams, rivers and estuaries before heading out to the open ocean. Depending on their species and population, salmon may spend anywhere from six months to five years in the ocean. Some travel thousands of miles during this time. Environmental factors like the availability of food, water temperature, river flows (which influence dissolved oxygen), ocean acidification and pollution all play a role in long-term health of all salmon species.

An additional challenge facing salmon is the destruction of their traditional spawning grounds through man-made structures, deforestation, climate change and habitat encroachment.

Policy action on behalf of salmon

One of the important conversations taking place around local salmon recovery is the improved operation or even removal of man-made structures, like dams, on salmon-bearing rivers. The Aquarium continues to advocate for science-based policies that can help conserve our marine environment, and recently took a position supporting the removal of the four lower Snake River dams to help recover and restore critically endangered salmon populations.

Salmon recovery and the lower Snake River dams

The Columbia River basin once saw 10 to 16 million salmon return to spawn, with the Snake River—the Columbia’s largest tributary—welcoming over 4 million returning salmon¹. But the cumulative impacts of habitat loss, climate change impacts on ocean temperatures, and the construction of 14 federal dams throughout the basin have nearly decimated these fish populations.

According to the 2017 ESA Recovery Plan, by the early 1990s, “abundance of naturally produced Snake River spring/summer-run Chinook salmon had dropped to a small fraction of historical levels.” Many salmon populations in the Columbia/Snake basin have already gone extinct, and nearly all remaining ones are listed as either endangered or threatened under the Endangered Species Act (ESA).

Unlike other dams in the basin, the four lower Snake River dams are not necessary for flood protection. In part for that reason, they have been the focus of discussions about potential dam breaching (removing the earthen embankments and putting other infrastructure out of commission) for more than two decades, with an eye to supporting salmon recovery. The science is clear: breaching the dams would significantly increase spring/summer Chinook returns. It would improve the chance of recovery for endangered Columbia and Snake River Chinook, sockeye and steelhead. It would also require both authorization and significant funding from Congress.

The connection to the orcas

Removing the four lower Snake River dams, as part of a broad suite of measures, could also improve salmon availability in the long term for the endangered southern resident orcas. These orcas spend part of the year off the coast, looking for food, and the science indicates that they rely on Chinook returning to the Columbia River in the spring.

For the orcas to recover, additional measures must also take place in the immediate to near term, including restoring and protecting salmon habitat in other places around the region, reducing vessel noise and disturbance, and reducing toxic runoff.

The draft environmental impact statement

In February, the agencies that operate the 14 dams released a draft environmental impact statement (DEIS). They found that breaching the four lower Snake River dams would result in the greatest benefits to endangered salmon. They did not select that as the preferred path forward for system operations, however, citing the loss of power generation at the dams, among other factors.

Seattle Aquarium position

We are deeply concerned about the declines in wild, endangered Chinook, sockeye and steelhead populations. The science points to breaching of the Lower Snake River dams as a way to improve the chance of recovery for salmon and steelhead populations in the Columbia River basin.

Broader local and regional conversations are needed to arrive at solutions in the basin that will work for both salmon and communities. We look to our governor and legislators to help continue these important conversations, and we thank the governor for the stakeholder engagement work that is already underway.

Opportunity to comment

The Seattle Aquarium will be submitting a comment letter on the DEIS. If you’d like to weigh in on the DEIS as well, you can submit a comment in the agencies’ online form by the April 13 deadline.

¹NMFS 2008 Recovery Plan for Southern Resident Killer Whales (Orcinus orca) at II-82