2021 Science Symposium Presentations
Nov 5, 2021
1st Talk – Dinner Debris: Genetic Clues Untangle Predator Diets
Kim Parsons – Molecular Genetics Lead – Conservation Biology Division, Northwest Fisheries Science Center NOAA, National Marine Fisheries Service
2nd Talk- Sperm Whale and Squid: The Prey Size Debate
Iliana Ruiz-Cooley – Faculty Researcher, Ensenada Center for Scientific Research and Higher Education Baja, California
Investigating how sperm whales (Physeter macrocephalus) select their prey and catch squid in the deep ocean remains a challenge. There is also limited information and observations on the feeding ecology and behavior of the giant squid, Architeuthis. More information exists on the foraging habits of highly voracious and migratory species like the jumbo squid, Dosidicus gigas, because they are of commercial importance. In this lecture, I will talk about the past, present and future efforts to investigate the diet of sperm whales and squid. I will highlightinteractions between predator and prey and provide insight into the debate on sperm whale prey size preferences.
3rd Talk – Technology to Ecology in the Deep-Sea
Jim Barry – Senior Scientist, Monterey Bay Aquarium Research Institute
Jim will provide an overview of deep-sea research off the California coast where the role of predation is still unclear, including deep-sea coral gardens, the “Octopuses’ Garden”, and evidence of whale predation at abyssal depths. Deep-sea coral and sponge gardens are found on seamounts and other rocky habitats around the world. The coral colonies in these gardens live in dark, cold waters far beneath the surface, reaching 3+ meters tall and living for centuries to millennia, akin to the old-growth forests on land. We know they are vulnerable to deep-sea trawling and other human activities, but what are the natural threats to these long-lived corals? Using remotely operated vehicles, time-lapse cameras, and oceanographic sensors, we are evaluating the effects of sea stars and other predators on their growth and survival.
The discovery of the Octopuses Garden https://sanctuaries.noaa.gov/magazine/4/octopus- garden/ during an Ocean Exploration cruise a few years ago led to research to understand why 10,000 octopuses breed in aggregations in abyssal hydrothermal warm springs at the base of Davidson Seamount. Jim will discuss how we have been able to study these aggregations and how these animals benefit from warm springs to promote breeding success. Exploration in the vicinity of the Octopuses Garden at over 2 miles depth also found evidence of whales feeding on the bottom. Pits formed by beaked whales as they attack deep sea prey (probably large fishes) were found at the base of the seamount more than 2 miles beneath the surface. Will these whales also feed on brooding octopuses at the Octopuses’ Garden?
Nov 6,2021
Talk 1 – Pacific Herring: Past and Present
Eleni Petrou – Post-Doctoral Researcher, University of Washington
Steve Johnson – Alaskan Native Naturalist and story teller
Forage fish are key links in coastal food webs, transferring energy from lower to higher trophic levels. In the North Pacific ecosystem, Pacific herring (Clupea pallasii) are one of the most abundant forage fish and are ecologically, culturally, and economically important. People have used herring as a food resource for millennia, and herring bones are frequently encountered in archaeological sites along the Pacific Northwest coast. Given the importance of herring to the coastal ecosystem and human livelihoods, there is considerable interest in sustainably managing the fisheries which target this species. However, in some geographic regions herring biomass and spawning activity have contracted in recent decades, leading to declining subsistence harvests and concern over the status of herring populations. In this talk, I will describe how genetic data are being used to study the importance of diverse herring populations to the diets of endangered salmon and to the food systems of Coast Salish and Tlingit ancestors. I will also discuss ongoing research on the genetic population structure of herring in Sitka Sound that is being done in partnership with the Sitka Tribe of Alaska.
Talk 2- Juvenile Sablefish: Pint-Size Predators
Matt Callahan – University of Alaska Southeast
Juvenile sablefish are pint-sized predators with prodigious appetites. They follow a “see food diet”, devouring whatever they can fit in their mouths. Their menu includes herring and salmon smolts, but also junk food prey like jellyfish. Juvenile sablefish are far from the top dog in the food chain and serve as prey to adult salmon and other large fish. Warming oceans have been good news for sablefish, leading to record numbers of hungry juveniles in Alaskan waters during recent marine heatwave years.
Talk 3 – Unique Advantages of Cold-Water Sharks
Dr. Danny Coffey – Assistant Research Scientist, Harte Research Institute for Gulf of Mexico Studies at Texas A&M University-Corpus Christ
Sharks have been in an evolutionary “arms race” with their prey for millions of years. Some sharks evolved unique adaptations that enable them to undertake extensive migrations to pursue prey unreachable to other predators. Even these formidable predators have physiological limitations creating barriers in an otherwise featureless open ocean, which will impact accessibility to other prey. To overcome challenges associated with direct observation of natural predator and prey behavior, the development of animal- borne electronic devices has allowed us to remotely observe the movements of sharks across diverse habitats, leading to significant breakthroughs in our understanding of their ecology and physiology. Here, we will explore how mammal-like muscles power swimming in a cold-water shark and follow an elusive “living fossil” into the deep sea.
Nov 7, 2021
Talk 1 – Small Krill Feed a Big Ocean
Rob King – Marine Research Facility Specialist, Marine Conservation and Management | Australian Antarctic Division
Antarctic krill are often regarded as the keystone species of the Southern Ocean ecosystem. This means that this single species strongly influences the ecosystem and many air breathing predators in this ecosystem do rely on Antarctic krill being available in vast numbers as their primary food source at one time of the year or another. While krill are not the only food source in the southern Ocean, they dominate the environment and they are the focus of the largest Antarctic fishery. Therefore understanding krill biology and the predators that rely on krill is key to ensuring the rational and sustainable use of Antarctic krill and for ensuring the conservation of the ecosystem. In this talk we will explore what krill are, their finely tuned life cycle, the threats they face and what the large gaps are in our understanding of krill. We will build on this to look at how we are attempting to understand krill both on the individual level and as a schooling super organism and how the behaviour of krill influences the predators that rely on them. We will also examine some of the technologies we are deploying to better understand krill and krill predators.
Talk 2 – Listening to Whales: A Story of Death & Discovery
Amy Willoughby’ – Research Scientist, University of Washington’s Cooperative Institute for Climate, Ocean and Ecosystem Studies (CICOES) and NOAA Fisheries’ Alaska Fisheries Science Center
Bowhead whales found in Arctic waters off northern Alaska (northeastern Chukchi and western Beaufort seas) have been migrating between the Bering Sea and Beaufort Sea for millennia. Why animals make long annual migrations has always interested scientists. Because sea ice in northern Alaska waters was thought to limit killer whale access, some scientists thought bowheads migrated out of the Bering Sea each spring to avoid being eaten by killer whales and that, once in northern Alaska waters, bowheads were likely safe from predation. And maybe they were, but a new study found that may not presently be the case. This study focused on dead bowhead whales who have a story to tell — a story about their own death. By examining photos of bowhead whale carcasses, scientists looked for clues to determine how the whales may have died. In all, 33 bowhead carcasses were examined. Eighteen carcasses told a story of probable killer whale predation. Killer whales preying on bowheads in this portion of their migratory range was a new discovery for science and an important piece of information on bowhead whale life history. The loss of sea ice in recent years likely allows killer whales easier access to hunt bowheads in northern Alaska. As the Arctic becomes more accessible for commercial fishing and marine traffic, this information can be used to identify changes in bowhead whale mortality and can help scientists and Alaska Native communities make informed management decisions to conserve bowheads for future generations.
I welcome you to come learn how we found and photographed bowhead whale carcasses and discovered that killer whales are preying on bowheads in locations scientists did not know about. Maybe you will be the first to witness killer whales hunting bowhead whales in the northeastern Chukchi or western Beaufort seas and publish it!
Talk 3 – Tiger (sharks) in the grass: the ecological role and importance of a top ocean predator.
Dr. Michael Hiethaus, – Executive Dean, College of Arts, Sciences & Education Professor, Department of Biological Sciences, Florida International University
Predator-prey interactions are a critical part of an animal’s life and also can shape the dynamics of ecosystems. These interactions, however, can be difficult to study for whales, dolphins, and other ocean animals. In this talk, we will explore multiple aspects of the game between predators and prey. We will start discussing the behavioral tactics predators use to try to catch a meal and prey deploy to avoid becoming one, focusing especially on interactions between tiger sharks and their marine mammal prey in Australia and humpback whales in Southeast Alaska. Next, we will investigate how the behavioral decisions that prey make to reduce their risk of being eaten – and not just the number of prey that are eaten by predators – can affect entire ecosystems.