Joseph Tomoleoni
Biography
Joe is a USGS biologist that is broadly interested in the ecology of coastal marine communities, particularly the influences of vertebrate predators on community structure. Most of his field research has focused on sea otter populations around the Northeastern Pacific Ocean. His past and current study sites focus mostly on Central and Southern California (including the Channel Islands), but also include many other locations around the Northeast Pacific like the Aleutian Islands, Southeast and Southcentral Alaska, and Washington. These studies are designed to better understand the suite of direct and indirect interactions between sea otters and other species in the nearshore environment. Joe and his colleagues use this model system to elucidate the influence of high-trophic-level consumers on the organization of the communities in which they live. Their research questions aim to investigate various aspects of sea otter behavioral ecology including: foraging trends, activity budgets, movement patterns, survival, and reproduction. The information gathered from their research helps to obtain a better understanding of sea otter biology, which, through species interactions with biotic and abiotic factors in their environment, advances our knowledge base for entire nearshore marine ecosystems.
In addition to sea otter population studies, Joe's fieldwork also includes intertidal and subtidal surveys of nearshore communities, as well as dive work to capture and tag sea otters and collect data or samples that help us better understand the link between otters, kelp forests, estuaries, and people. Joe and his USGS colleagues are also the lead agency conducting the annual sea otter census in California, which monitors population change and distribution over time. Joe also serves on the USGS National Dive Safety Board as the Southwest Region Dive Safety Officer.
EDUCATION
MS, Marine Affairs & Policy/Marine Biology & Fisheries, University of Miami Rosenstiel School of Marine & Atmospheric Science (FL), 2007
BS, Marine Biology, University of Miami (FL) 2005
Science and Products
California Sea Otter Stranding Network
The California Sea Otter Stranding Network is part of the USGS effort to monitor southern sea otters (Enhydra lutris nereis) and provide data to the U.S. Fish and Wildlife Service. WERC's sea otter team works with multiple institutions and partners to report, recover, and examine stranded sea otters. In addition, instructions on how to report a stranded sea otter are included in this webpage...
California Sea Otter Surveys and Research
WERC collaborates with other research scientists to conduct annual population surveys of the southern sea otter -- a federally listed threatened species. In coordination with the California Department of Fish and Game and other institutions, ongoing surveys and research continues to inform the southern sea otter recovery plan for the U.S. Fish and Wildlife Service, and contributes to our...
Population Biology and Behavior of Sea Otters
WERC's sea otter researchers are developing and utilizing a variety of methodological and analytical tools to understand the causes of biological and ecological trends in sea otter populations, and to predict the ecological consequences of management practices on these populations and their ecosystems.
Pacific Nearshore Project
Sea otters are crucial indicators of the health of our nearshore waters and coastal resources, from kelp forests to fisheries. What clues does the sea otter's decline hold for our knowledge of ecosystem and global change? WERC's sea otter team and U.S. and Canadian researchers have teamed together to investigate.
Relevance to USGS Missions:
This research project has direct...
Santa Cruz Field Station
Scientists at the Santa Cruz Field Station study sea otters and seabirds in their environment. The USGS Western Ecological Research Center has two research missions based in the Santa Cruz region:
Habitat features predict carrying capacity of a recovering marine carnivore
The recovery of large carnivore species from over‐exploitation can have socioecological effects; thus, reliable estimates of potential abundance and distribution represent a valuable tool for developing management objectives and recovery criteria. For sea otters (Enhydra lutris), as with many apex predators, equilibrium abundance is not constant...
Tinker, M. Tim; Yee, Julie L.; Laidre, Kristin L.; Hatfield, Brian; Harris, Michael D.; Tomoleoni, Joseph; Bell, Tom W.; Saarman, Emily; Carswell, Lilian P; Miles, A. Keith Exposure to domoic acid is an ecological driver of cardiac disease in southern sea otters
Harmful algal blooms produce toxins that bioaccumulate in the food web and adversely affect humans, animals, and entire marine ecosystems. Blooms of the diatom Pseudo-nitzschia can produce domoic acid (DA), a toxin that most commonly causes neurological disease in endothermic animals, with cardiovascular effects that were first...
Moriarty, Megan E; Tinker, M Tim; Miller, Melissa; Tomoleoni, Joseph; Staedler, Michelle M.; Fujii, Jessica A.; Batac, Francesca I.; Dodd, Erin M.; Kudela, Raphael M.; Zubkousky-White, Vanessa; Johnson, Christine K. Examining the potential conflict between sea otter recovery and Dungeness crab fisheries in California
Human exploitation of marine mammals led to precipitous declines in many wild populations within the last three centuries. Legal protections enacted throughout the 20th century have enabled the recovery of many of these species and some recoveries have resulted in conflict with humans for shared resources. With legal protections and reintroduction...
Boustany, Andre M.; Hernandez, David; Miller, Emily A; Fujii. Jessica; Nicholson, Teri E.; Tomoleoni, Joseph; Van Houtan, Kyle S.
Southern (California) sea otter population status and trends at San Nicolas Island, 2017–2020
The southern sea otter (Enhydra lutris nereis) population at San Nicolas Island, California, has been monitored annually since the translocation of 140 sea otters to the island was completed in 1990. Monitoring efforts have varied in frequency and type across years. In 2017, the U.S. Navy and the U.S. Fish and Wildlife Service initiated a sea...
Yee, Julie L.; Tomoleoni, Joseph A.; Kenner, Michael C.; Fujii, Jessica; Bentall, Gena B.; Tinker, M. Tim; Hatfield, Brian B.
Kelp forest monitoring at Naval Base Ventura County, San Nicolas Island, California: Fall 2018 and Spring 2019, fifth annual report
IntroductionKelp forests and rocky reefs are among the most recognized marine ecosystems and provide the primary habitat for several species of fishes, invertebrates, and algal assemblages (Stephens and others, 2006). In addition, kelp forests have been shown to be important carbon dioxide sinks (Wilmers and others, 2012) and are an important...
Kenner, Michael C.; Tomoleoni, Joseph A. Robust age estimation of southern sea otters from multiple morphometrics
Reliable age estimation is an essential tool to assess the status of wildlife populations and inform successful management. Aging methods, however, are often limited by too few data, skewed demographic representation, and by single or uncertain morphometric relationships. In this study, we synthesize age estimates in southern sea otters ...
Nicholson, Teri E.; Mayer, Karl A.; Staedler, Michelle M.; Gagne, Tyler O; Murray, Michael J.; Young, Marissa A; Tomoleoni, Joseph; Tinker, M Tim; Van Houtan, Kyle S. Locality note for rubber boa
CHARINA BOTTAE BOTTAE (N. Rubber Boa), USA: CALIFORNIA: Monterey Co.: Landels-Hill Big Creek Reserve, east side of Hwy. 1, 80 km (50 miles) south of Carmel, Calif., (36.0719055 N 121.5991555 W) 19 June, 2009; (36.0703611 N 121.5982222 W) 06 July 2009; (36.9516666 N 121.5991944 W) 27 July 2009. In chronological order, photo vouchers MVZObs:...
Tomoleoni, Joseph; Hoyer, Richard F Emergence of a zoonotic pathogen in a coastal marine sentinel: Capillaria hepatica (syn. Calodium hepaticum)-associated hepatitis in southern sea otters (Enhydra lutris nereis)
Capillaria hepatica is a globally distributed zoonotic nematode parasite that most commonly infects feral and native rats. Soil contact, pica, and living in close proximity to rat populations are risk factors for human infection. Larval nematodes and eggs that were morphologically consistent with C. hepatica were observed...
Miller, Melissa A.; Duignan, Padraig J; Dodd, Erin; Batac, Francesca; Staedler, Michelle M.; Tomoleoni, Joseph; Murray, Michael J.; Harris, Heather; Gardiner, Chris Spatial epidemiological patterns suggest mechanisms of land-sea transmission for Sarcocystis neurona in a coastal marine mammal
Sarcocystis neurona was recognised as an important cause of mortality in southern sea otters (Enhydra lutris nereis) after an outbreak in April 2004 and has since been detected in many marine mammal species in the Northeast Pacific Ocean. Risk of S. neurona exposure in sea otters is associated with consumption of clams and soft-sediment prey and...
Burgess, Tristan; Tinker, TIm M; Miller, Melissa A.; Smith, Woutrina A.; Bodkin, James L.; Murray, Michael J.; Nichol, Linda M.; Saarinen, Justin A.; Larson, Shawn E.; Tomoleoni, Joseph; Conrad, Patricia A.; Johnson, Christine K.
Kelp forest monitoring at Naval Base Ventura County, San Nicolas Island, California: Fall 2017 and Spring 2018, Fourth Annual Report
To assess and track changes to the rocky subtidal communities surrounding San Nicolas Island, the U.S. Navy entered into an agreement with the U.S. Geological Survey (USGS) in 2014 to conduct an ecological monitoring program at several sites around the island. Four permanent sites—Nav Fac 100, West End, Dutch Harbor, and Daytona 100—were...
Kenner, Michael C.; Tomoleoni, Joseph Species recovery and recolonization of past habitats: Lessons for science and conservation from sea otters in estuaries
Recovering species are often limited to much smaller areas than they historically occupied. Conservation planning for the recovering species is often based on this limited range, which may simply be an artifact of where the surviving population persisted. Southern sea otters (Enhydra lutris nereis) were hunted nearly to extinction but recovered...
Hughes, Brent B.; Wasson, Kerstin; Tinker, M Tim; Williams, Susan L; Carswell, Lilian P; Boyer, Katharyn E.; Beck, Michael W.; Eby, Ron; Scoles, Robert; Staedler, Michelle M.; Espinosa, Sarah; Hessing-Lewis, Margot; Foster, Erin U.; Beheshti, Kathryn; Grimes, Tracy M; Becker, Benjamin H.; Needles, Lisa; Tomoleoni, Joseph; Rudebusch, Jane; Hines, Ellen Marie; Silliman, Brian R
California sea otter (Enhydra lutris nereis) census results, spring 2019
The 2019 census of southern sea otters (Enhydra lutris nereis), also known as California sea otters, was conducted from early May to early July along the mainland coast of central California and in April at San Nicolas Island in southern California. The range-wide index, defined as the 3-year average of combined counts from the mainland range and...
Hatfield, Brian B.; Yee, Julie L.; Kenner, Michael C.; Tomoleoni, Joseph A.