Thesis Defense by Heather Barrett-May 24th

The energetic cost of human disturbance on the southern sea otter (Enhydra lutris nereis)

A Thesis Defense by Heather Barrett

Vertebrate Ecology Lab

Friday, May 24th, 2019 at 4 pm

MLML Seminar Room

Heather Barrett is a master’s student under Dr. Gitte McDonald in the Vertebrate Ecology Lab. She graduated from the University of California Santa Cruz in 2009 with a B.S. in Ecology and Evolution and studied abroad in England, France, and Belize. Prior to her research at Moss Landing Marine Labs, Heather interned with the Monterey Bay Aquarium’s Sea Otter Research Program, worked abroad in education, managed data entry and fieldwork with California Department of Fish and Wildlife’s long-term biodiversity assessment in Northern California, and assisted with whale shark research in Mexico. Heather currently is a team member with Sea Otter Savvy and hopes to continue her work with research, science communication, and outreach.

Thesis Abstract:

With increased human populations and tourism in coastal areas, there is increased potential for disturbance of marine wildlife.  Impacts of disturbance are not well understood for many coastal species, such as the southern sea otter (Enhydra lutris nereis). Due to high metabolic rates, sea otters are at particular risk of increased energetic costs due to human disturbance. To investigate effects of disturbance, behavioral scans were conducted over three years to record sea otter activity in response to potential disturbance stimuli at three locations in California: Monterey, Moss Landing, Morro Bay. We developed a hidden Markov model to examine how activity varies as a function of location, time of day, group size, pup to adult ratio, habitat (kelp vs. open water), and occurrence of and proximity to potential disturbance stimuli. We combined our results with published estimates of activity-specific metabolic rates, translating changes in activity state into corresponding energetic costs. Our results indicate that the effects of disturbance stimuli on sea otter behavior are location specific, and vary non-linearly with distance from disturbance stimuli. Our model quantifies the distance-disturbance relationship, and calculates the distance at which the likelihood of disturbance is low: averaged across locations, there is <10% potential disturbance when stimuli are >54 meters away. We also estimate energetic costs(kJ) associated with various disturbance scenarios: for example, daily energy expenditure is expected to increase by 212.53kJ ± 15.75, 154.64kJ ± 13.84 and 62.54kJ ± 5, for Monterey, Moss Landing and Morro Bay, respectively, with six small-craft approaches of 20m for a 27.7kg male otter in kelp with 10 otters and a pup ratio of 0.25. Our analyses represent a novel approach for estimating behavioral responses and energetic costs of disturbance, thereby furthering our understanding of how human activities impact sea otters and providing a sound scientific basis for management.

Listen Up! Our grad students are doing some awesome outreach

Listen Up!

Brijonnay Madrigal is a student in the Vertebrate Ecology Lab who studies bioacoustics of Risso's Dolphins in the Monterey Bay.  To share her love and knowledge of the incredible sounds of marine mammals, Brijonnay has developed an outreach program in the Monterey Bay area. "Listen Up!" is an interactive program that teaches K-12 students about marine mammals, acoustics, sounds in the ocean, and conservation. The program has already reaches 10 elementary schools, 1 middle school, and 10 high schools in the area.

 

Alison Stimpert gives insight on government shutdown

January 11, 2019

MLML's Dr. Alison Stimpert talks about how the government shut down is affecting scientists in this NPR article.

Excerpt:

Alison Stimpert, a marine biologist with California State University, writes, "Even though I am continuing to work, many of my collaborators (USGS, NOAA) are furloughed and projects we are working on together cannot move forward." She says that means "project planning meetings are being delayed, as well as permit applications for upcoming work."
Stimpert studies bioacoustics — "acoustic behavior and effects of noise on marine species," she explains — in waters off of California, Hawaii, Massachusetts, Alaska and Antarctica. She says that in some cases, the shutdown means she may have to reorganize some travel or wait to start a phase of research until collaborators can work. In other areas, it might have more serious implications: "We might miss an opportunity to deploy an instrument, which makes us miss collecting an entire season of data." And Stimpert says that if she or her collaborators have future federal funding delays, it could mean that "I can't purchase an instrument that I need, but might (and I am not alone in this) mean my other funding runs out and I can no longer fund my position, making me lose my benefits."

MLML’s Dr. Alison Stimpert co-authored recently published study on blue whale behavior

Dr. Alison Stimpert

Research Faculty member Dr. Alison Stimpert serves a co-author for a large collaborative study on blue whales that has revealed preferences in the direction (right vs left handedness) that the whales will roll during lunge feeding.  The study was published in Current Biology on November 20th, 2017 and featured in UCSC News, as well as The Guardian.  You can download the paper for free for 50 days here.