Friday, November 16, 2018

Northern elephant seal stranding on Marrowstone Island

Marine mammal necropsied, skeleton preservation underway

Being the brand new Marine Mammal Stranding Network AmeriCorps at the Port Townsend Marine Science Center, every stranding call is new and exciting. So when the line rang on October 31 for an approximately 14-foot long northern elephant seal that had washed ashore, I was more than thrilled for the opportunity.

This seal was originally reported the day prior on the smartphone app iNaturalist, which serves as an online social network for citizen scientists by creating a platform for sharing and mapping local natural observations. Shortly after this posting, our stranding line received a phone call officially reporting the animal to us.

Several hours later, the entire crew of new PTMSC AmeriCorps staff departed to learn and practice what to do with our first dead stranded mammal.

The animal was found north of Liplip Point on the southeast corner of Marrowstone Island. We determined it to be an adult male northern elephant seal with no obvious external injuries.

This particular area of beach is very remote and difficult to get to, but thankfully we had received permission to use the stairs of the land owner who reported the animal. Thus, on Halloween we began our trek down the excitingly precarious stairs you will see pictured to the right.

What truly amazed me (and I think I can speak for everyone else there) was the seal’s size. He measured 406 cm from the tip of his head to the tip of his tail. That’s over 13 feet! And that didn’t include his rear flippers.

Michael Siddel, Citizen Science Americorp member, and PTMSC 
Citizen Science Coordinator Betsy Carlson 
examining the front flipper
While there, we worked with the two PTMSC volunteers who were called to respond to the seal and the individual who reported the mammal. This work included collecting data on the animal, such as: observations, quantitative data (e.g. weight measurements), and looking for the possibility of human interaction (i.e. any indications human activities may have affected their life or death).

Because the Marine Mammal Stranding Network works with the National Oceanic and Atmospheric Administration to collect and manage data on stranded marine mammals along our coasts, this information gathering process is crucial.

Almost immediately upon our return, rumors began floating on the possibility of gaining permission to do a necropsy and preserve the full skeleton as an education tool. By the following afternoon, this became a reality and plans were in the works to begin as soon as the next day.

Friday morning, the small team assembled and began a necropsy and flensing procedure under the guidance of Dyanna Lambourn, our go-to pinniped person at the Washington Department of Fish and Wildlife. Necropsies give us the opportunity to gain a better insight on the cause of death by acquiring samples to send to a lab, and the ability to look at the conditions of the internal organs.

The team of PTMSC volunteers and staff participating in the necropsy.
Currently, the bones have been moved to beneath our pier to begin the process of soft-tissue decomposition under water. Now, we wait until the bones are ready for processing before we can begin articulating the skeleton for exhibit. Stay tuned for exciting developments!

Volunteer Bruce Carlson transporting the seal to its new temporary resting place. Photo credit: Wendy Feltham 

Written by Mandi Johnson, Americorps Volunteer Program Educator

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