The More the Murrier
Welcome back to the another adventure here in Newport, Oregon! I want to keep you updated on the world of the murres at Yaquina Head. In the past couple of weeks, I’ve been working part time with the Seabird Oceanography Lab from Oregon State University, helping the team with several projects. One of these projects focuses on the monitoring of the common murres. Everyday, we’re keeping a close eye on their reproduction success by looking for new eggs and chicks! Just recently I had to draft the mid season report for all of our projects, and I’d like to share some news on how the common murres are doing.
Something that isn’t new with the murres is the presence of the bald eagles. While I work with the Bureau of Land Management at Yaquina Head during the day time I hardly see the eagles come over Colony Rock, where the murres stay on their eggs. This would’ve led me to believe that the murres were doing a great job on staying on the rocks as their predators were not present. When we monitor their eggs early in the morning, however, we see a different picture. The bald eagles return to Colony rock before the break of dawn in the morning and capture their prey. Initially, I believed there were fewer number of disturbances observed for this year in comparison to the past recent years. When we compared the data, we found out that it wasn’t the case. The number of disturbances this year compared to last year are just about the same!
Let me paint a picture that illustrates the struggle of the common murre colony. The common murres fly to the top of the rocks at Yaquina Head to lay their eggs and incubate them until they hatch. This unfortunately creates a large group of “sitting ducks” for their predators, specifically the bald eagles around the area. The adult bald eagles fly to Colony rock to catch a common murre and either eat their prey on the same rock or carry it away. Adults are usually accompanied by some juvenile bald eagles as well. The presence of the predators causes distress and mayhem for the murres, causing many of them to flush out of the rock and leaving their eggs and chicks vulnerable to other scavengers. Western gulls, crows, and even brown pelicans will take advantage of the chaos and steal eggs from the rocks.
What makes this year somewhat different from the rest is that more murres are sticking to the rock, despite the dangerous presence of bald eagles! This is an interesting observation that leads to possible hypothesis. Perhaps there are more murres that hold a greater incentive to protect their eggs, which may lead to a natural selection for “brazen” murres. Maybe this year there are sufficient resources for the adults to invest their energy in protecting their eggs and offspring. It’s hard to say right now why the murres are dedicating more time to their eggs despite immediate danger, but I hope to see some progress (and baby chicks) to keep you updated on this story. Stay tuned!