Week 10: Least Tern Monitoring

In a previous blog I mentioned that the California Least Terns, the federally endangered birds, are back from the south and we have begun monitoring at the Least Tern Colony in Venice Beach. The first day that I participated in monitoring we did not find tracks or scrapes-which the birds do in preparation for nesting. Several weeks passed and I finally get to see their tiny webbed feet tracks and 4-6inch scrapes in the sand! We have not found any eggs yet but it is still early in the breeding season. We will continue to to monitor once a week until we find Least Tern eggs and we will also observe and record any human and animal disturbances.

This week I also attended the Southern California Academy of Sciences annual meeting at Loyola Marymount University and I attended the Urban Ecology session. I learned about undergraduate and graduate projects that focused in urban science, education, and justice & ethics-all topics that I’m extremely interested in. I had the opportunity to hear Peter Auger and his grad students’ “Development of a Promising New Endangered Species Predator Aversion System” presentation. They are studying effective ways to reduce crow predation on the California Least Terns eggs. I’ve been to the study site multiple times (the Least Tern Colony) I have seen their study materials (camera station and egg replicas) but this is the first I’ve seen the presentation which was relevant and significant to me since I’m involved with Least Tern conservation. For four years, from 2009-2013, there had been no reproductive success  at the Tern colony due to Crow predation. Auger conducted his first study in 2013 by placing chemical emetic quail eggs which would make the crows vomit after digestion. However, this method was not effective as there was still zero reproduction success that year. They said it might’ve been due to the lag time of digestion and getting sick that the crows did not correlate sickness with the consumption of emetic eggs. Last year, they conducted a different method in which Auger and his students’ created electric quail and tern eggs that would shock the crows. So far this method has been successful as there were 80-100 successful California Least Tern fledglings towards the end of the last breeding season. This year, they are continuing the study by using replicas of quail and tern eggs, different station placements, and other method adjustments. When we monitored this week, we did note a few crows flying across the colony as if they were looking for eggs. We will see at the end of this breeding season whether the experiment will be successful again or not. After a few shocks, it appeared that crows would only walk at the colony ignoring the eggs- a behavior we hope to see once the Least Tern lay their actual eggs.  Crows are intelligent birds so I’m curious to know if at some point they will be able to tell the difference between the real eggs and the electrical replicas. As mentioned, we will see at the end of the summer when the results are in!

Attending the Southern California Academy of Sciences annual meeting was a great experience for me because I was inspired by the local projects on urban resilience. In addition, I also observed that there were very few latinos presenting or attending this meeting which reminds me the low number of underrepresented students that hold a bachelor’s degree let alone a graduate or a doctorate degree (https://www.census.gov/prod/2012pubs/acsbr10-19.pdf). This encouraged me to keep moving forward and to begin now. I do not know when and on what but I do know that I do want to pursue my masters degree. And, I’m really liking LMU- because of its urban resilience program and by its location (right next to the beach!).

Top left: We use devices to track our steps during our monitoring. Teams of two walk in each grid in zigzags. This was the result of my team.  Bottom left: Me, walking carefully and looking for Tern nests and eggs.  Top Right: a decoy of a tern and the electric eggs used for Peter Augers' study.  Bottom Right: California Least Tern Tracks. They are small and webbed!

Top left: We use devices to track our steps during our monitoring. Teams of two walk in each grid in zigzags. This was the result of my team.
Bottom left: Me, walking carefully and looking for Tern nests and eggs.
Top Right: a decoy of a tern and the electric eggs used for Peter Augers’ study.
Bottom Right: California Least Tern Tracks. They are small and webbed!

How Peter Augers' stations are set up at the Least Tern Colony.

How Peter Augers’ stations are set up at the Least Tern Colony.

Check out this collage of this predator-prey moment. We saw this gopher snake eat California Towhee chicks at the Baldwin Hills Scenic Overlook. I felt the heart-break of the mama Towhee but moments like these the Lion Kings theme song, “Circle of Life” begins playing in my head.

Top left: A picture of the gopher snake poking his head out. Bottom left: How the nest resulted when the snake left.  Right: The snake slithering away from the nest where it ate the two CA Towhee babies. You can see the mama Towhee a few feet away from the snake!

Top left: A picture of the gopher snake poking his head out.
Bottom left: How the nest resulted when the snake left.
Right: The snake slithering away from the nest where it ate the two CA Towhee babies. You can see the mama Towhee a few feet away from the snake!

emilycobar
emilycobar@gmail.com
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