News & Events
This section contains current news and events as well as project team biographies and a telemetry blog. Discover where telemetry tags show that juvenile Steller sea lions are dying in Alaska. See a recent map of mortality events below.
Recent Mortality Events
Updated on August 10th, 2012
As of July 31st, 2012, we have detected 16 mortality events. At least 14 of these 16 events were due to predation. In two cases, we did not receive enough data to determine the likely cause of mortality. In three cases the data suggests that the animals died by predation from Pacific sleeper sharks.
This map of mortalities is based on satellite locations from the Life History Transmitter. Each dot indicates a place where a juvenile Steller sea lion has died. The red dots indicate Steller sea lions that have died due to predation, likely from transient killer whales. The blue dots also indicate sea lions that have died from predation, but in this case most likely by Pacific sleeper sharks. The white dots indicate insufficient information to determine a cause of death.
For more information, see the "Map of Mortalities" page under 'What Are We Learning?'.
Telemetry in the News
publication resulting from the LHX tag project was published today
in the online Open Access journal PLoS
ONE. The paper presents a new population model that analyzes how predation
rates may change as the abundance of sea lions varies.This model is what
we call a qualitative conceptual model. This means it is a model that
presents 'what if' scenarios, rather than a quantitative model that attempts
to make specific and accurate predictions for certain circumstances. The
conceptual model is a thinking tool. However, our model suggests some
very interesting 'what if' scenarios. Specifically, the model suggests
that predation may be the main driver behind the western Steller sea lion
population trends. Furthermore, the model suggests that this effect may
come about because predators may focus their efforts on young sea lions.
This could result in fewer females surviving to sexual maturity and having
pups. This in turn could lead to the appearance of reduced birth rates
- which have been suggested as drivers of the population trends. Our model
instead suggests that this effect may actually stem from predation, and
that birth rates have not changed at all. This publication is available
for the general public to download and freely distribute. Click
here to download this publication from the PLoS ONE website.
Check out this nicely done write-up on our project on the website of the North Pacific Universities Marine Mammal Research Consortium:
Oregon Governor and First Lady Learn about Life History Transmitters
Oregon Governor John Kitzhaber and First Lady Cylvia Hayes visited the Pinniped Applied Ecology Research Laboratory (PEARL) as part of their visit to the Marine Mammal Institute at the Hatfield Marine Science Center. “Governor Kitzhaber and First Lady Hayes have a genuine interest in marine science,” says Dr. Markus Horning of PEARL. Dr. Horning showed the Governor and First Lady the Life History Transmitter Tags that he implants in Steller sea lions to study how they are dying. “They seemed to find the project interesting and fascinating,” says Dr. Horning. Dr. Horning described how the tag detects mortality and how it distinguishes predation and non-predation events. “The Governor and First Lady even participated in a impromptu brainstorming session related to recent mortality events,” chimes Dr. Horning. Dr. Horning explained that the latest Steller sea lion death may likely be due to predation by a shark. The Governor, First Lady, and Dr. Horning considered how to modify a sensor on the tag to register that it is in a shark’s stomach.
Photo: (L to R) Dr. Markus Horning, Governor Kitzhaber, Gil Sylvia (Superintendent of the Coastal Oregon Marine Experiment Station), Cylvia Hayes (the Governor's partner and First Lady of Oregon). Photographer: Heather Bene, Oregon State University Government Relations.
Last Capture Cruise Ended with an Exciting Re-sight
This June marked the 15th and possibly last capture cruise for the Life History Transmitter Project. On June 2nd, a team from the Alaska Sea Life Center and Oregon State University went out to capture the last four juvenile Steller sea lions of the project at Glacier Island in Prince William Sound. At the haul-out they had a pleasant surprise, the team saw a seven-year-old female who received one of the first two LHX implants. (She is visible in the photo below as =908.) “She appeared to be healthy and doing well. We hope we will see her with pups next year,” said Dr. Markus Horning. Scientists brand the animals to be able to identify them later and monitor their survival. They also saw two other animals that had received implants. Since the first capture cruise in August 2005, researchers captured 60 juvenile Steller sea lions and 37 received implants. "In this phase of the project, we are simply waiting for mortality events to occur,” Dr. Horning explains. Researchers anticipate that the cause of death in Steller sea lions may change as the study animals age.
This is one of the first two LHX-implanted animals, a female that was released in November of 2005 at the age of about 1.5 years. She is now 7 years old and doing well. She is marked with these characters, =908.
The success of these capture cruises depends on many individuals and staff at the Alaska SeaLife Center including the husbandry staff.
Dr. Bill Hanshumaker Presents Curriculum at NW NAME
Dr. Bill Hanshumaker will be presenting a poster at Northwest Aquatic and Marine Educator Conference in Port Angles, Washington about Studying Sea Lions Using Telemetry, the companion curriculum to this website. The conference will take place on July 13-16, 2011 at the Olympic Park Institute. We invite educators to attend Bill’s poster presentation and learn more about what the curriculum and website have to offer!