Every year the Seattle Aquarium participates in the annual Washington sea otter survey, organized and run by the United States Fish and Wildlife Service (USFWS). The Aquarium has participated in the sea otter survey since 2001 and has expanded on this important work by conducting our own sea otter foraging research, including bimonthly surveys, along Washington’s outer coast.
Our research team includes Conservation Research Manager Dr. Shawn Larson, Animal Care Specialist Caroline Hempstead, Research Technician Amy Olsen, Animal Care Specialist Aubrey Theiss, and visiting scholar Jennifer VanBrocklin. Their job is to observe sea otter foraging behavior in the wild to better understand what the otters are eating, the energy they must expend to hunt their prey and the general health and wellbeing of the resident population. By studying our local sea otters, we’re gaining a better understanding of the overall health of the ecosystem and the population levels of other species that sea otters rely on as a source of food.
Spotting sea otters in the wild isn’t as easy as you might think! View the video below and see how many otters you can count.
WHAT’S IT LIKE TO BE A RESEARCHER?
How did you do at counting sea otters? Ever wonder what it’s like to be a researcher out in the field? Below is a recap from our team as they counted a record number of sea otters during the 2019 sea otter census.
JUNE 24, 2019
After loading up with food, Amy, Shawn and Jennifer headed to the outer Washington coast along Highway 101. Caroline and Aubrey drove separately, because this year the Seattle Aquarium was directed to survey two different sites—South Beach Campground and Giants Graveyard. Because the survey didn’t officially begin until the following morning, the team had decided to collect some data for their own research by looking for sea otters that were foraging. Heading south, Amy, Shawn and Jennifer saw zero otters at a site called Side of the Road (literally a pullout along 101), two otters at Steamboat, four otters at Beach Four, 20 otters at Kalaloch Lodge, and over 160 otters at South Beach Campground. The only foraging otters were at South Beach Campground, and Caroline and Aubrey were already there collecting data when the others arrived. They were able to record 50 dives where otters were foraging for razor clams.
JUNE 25, 2019
The following day, the team split into different groups. Aubrey and Amy headed to South Beach Campground, while Shawn, Caroline and Jennifer went to Giants Graveyard. At South Beach Campground, they counted over 550 sea otters in separate rafts! They were also able to record 52 foraging dives, mostly for razor clams. The weather was clear, so the plane was able to fly overhead along the entire range and take photographs of the large rafts. Shawn, Caroline and Jennifer hiked the five miles round trip to Giants Graveyard over hills and through unmaintained forest trails. They arrived at least an hour before the plane because they had to secure ropes to climb up to the observation point to get an unobstructed view of the otters. Once in position, they were able to count 59 sea otters with many moms and pups when the plane flew over. Unfortunately, none were foraging, so they didn’t collect data for their own research, but they did get an accurate count for the survey.
JUNE 26, 2019
Today the teams partially switched, and Shawn, Aubrey and Amy headed to Giants Graveyard. Luckily the weather was good again so the plane was able to fly. They counted 55 otters, but unfortunately no foragers. Caroline and Jennifer counted 326 sea otters offshore at South Beach Campground and recorded 30 foraging dives.
JUNE 27, 2019
Finally, the weather turned. Clouds and heavy rain prevented the plane from flying, but the teams headed out to get final counts and foraging data. Aubrey and Amy revisited South Beach Campground and counted only 50 otters and recorded 25 foraging dives. Shawn and Jennifer went back to Giants Graveyard, where a group of kayakers broke up the raft before they were able to get a good count of the otters. Both harbor seals and sea otters were disturbed by this group of four kayakers—a good reminder that all marine mammals are protected by the U.S. Marine Mammal Protection Act, which states no one is to harass a marine mammal, such as flushing them from resting places or breaking up a raft of sea otters.
Overall this year’s survey was a success, with a great ground counting crew from the Seattle Aquarium and two days of flights and ground counts. Next the USFWS and WDFW have to count the otters from the plane pictures and compare them to the ground counts where available. The final survey will be the highest count on either day. Final results are pending. The last official survey was done in 2017 when there was a total of 2,058 sea otters counted throughout the range.
HOW MANY SEA OTTERS DID YOU COUNT?
Not as easy as it sounds, right? It takes patience and a sharp eye to get an accurate count. We have to confess: we don’t know exactly how many sea otters are in that video! Take a moment to challenge your friends on social media to see if you can come up with the same number.
If you’d like to learn more about the annual census and our sea otter foraging surveys, take a moment to watch the video below.