Category: Notes from the Field

BY ALEXA PIGGOTT

In early July, the Cormorant Oceanography Project seabird team, myself (Alexa Piggott), Adam Peck-Richardson, and Rachael Orben, traveled to the Columbia River Estuary, at the border of Oregon and Washington, to capture and tag adult Brandt’s cormorants. Our goal was to test the performance our latest GPS/GSM biologging tags made by Ornitela.

Brandt’s cormorants’ nest, roost, and forage near the mouth of the Columbia River. We were specifically targeting cormorants roosting on estuary channel markers, as these can be relatively easy locations to catch birds during the day. Over two days, we successfully deployed 6 biologging tags. Preliminary data, shows the cormorants moving and foraging near the mouth of the estuary and spending time at Cape Disappointment, WA.

We also spotted one of our newly tagged birds on the second day, resting on pilings with other cormorants and close to actively foraging Brandt’s and double-crested cormorants.

These tagged cormorants will collect detailed location and movement data, along with high quality profiles of water temperature, bottom soundings, surface currents (based on bird drift), and IMU data used to recover wave statistics. The data collected by these cormorants will be used to estimate bathymetry and circulation in the estuary and help calibrate and improve nearshore modeling.

Visualizations of these and previous tag deployments on cormorants in the Columbia River can be found on the Animal Telemetry network’s data portal.

The Cormorant Oceanography project is based at Oregon State University and funded by the Office of Naval Research.

By Adam Peck-Richardson

The Cormorant Oceanography Project made its first visit to the Hawar Islands, in the northern Arabian Gulf, in early December 2021. Myself (Adam Peck-Richardson) and collaborator Dr. Sabir Bin Muzaffar (United Arab Emirates University) spent four days visiting the Socotra cormorant colony at Rubd Al Shariqiya, a 1.5 km wide desert island surrounded by expansive shallow seagrass beds (and the world’s largest dugong aggregation). Unfortunately, the timing of our visit was later than originally planned and most of the cormorant chicks (10s of thousands) were very large and very mobile. This made it difficult to capture and tag adults at nests, but we were able to deploy four tags and gained valuable insights for further tagging work in 2022.

Data from the four tags immediately began streaming back to us (data are transmitted through cell phone network connections) and we are using this preliminary deployment to further improve tag design and performance. These GPS/GSM biologging tags, made by Ornitela (Vilnius, Lithuania), collect location and movement data and take detailed water temperature and depth measurements when the cormorants dive. Meanwhile, our oceanographer teammates at Oregon State University, led by Dr. Doruk Ardağ, have been spinning up a model of water temperature and circulation in the Arabian Gulf. The oceanographic data collected by cormorants are now being used to help calibrate and improve these complex regional models.

In 2022, we are planning to deploy additional oceanographic tags on Socotra cormorants at several colony sites throughout the region. These deployments will provide valuable data on population movements of Socotra cormorants and improve oceanographic modelling in the Arabian Gulf.

The Cormorant Oceanography project is based at Oregon State University and funded by the Office of Naval Research. Our work in Bahrain is made possible by logistical support from Dr. Abdulqader Khamis (University of Barcelona) and Dr. Humood Nasser (University of Bahrain), and administrative support from H. E. Sh. Ebrahim Alkhalifa and Rawan Suleiman (UNESCO – Arab Regional Centre for World Heritage). Local travel and logistics were coordinated with Sam Rowley and Nick Green (BBC – Natural History Unit) who are scouting for an upcoming project, Asia. Check out the brief clip below, from BBC’s Planet Earth, for an overview of how the Hawar Socotra cormorant colony fits into the Arabian Gulf’s desert-marine ecosystem.