By Aya Attal, NSF REU Intern, Portland State University
While spring is usually the season of change for most things, there’s been a lot of change over on the Oregon Coast this summer, too! A lot of change for me, certainly– my name is Aya Attal, and I go to school at Portland State University. However, I’ve been living in Newport this summer and working as an REU intern in Rachael Orben’s lab at Oregon State University, studying seabirds at Yaquina Head and Depoe Bay. And while there is a lot of change for me, there is even more change for the seabirds this summer; we’ve noticed a lot of improvement in the outlook of the breeding activities in the murres, cormorants, and gulls at Yaquina Head (Newport) and Pirate Cove (Depoe Bay).
A lot has happened over a few short weeks at Yaquina Head (Figure 1) this summer, even since the last update on June 11th.
Figure 1. Yaquina Head at 6am. Whale Rock can be seen at the bottom. The lone (?) murre chick at Yaquina Head is located in a protected crevice low on the rock.
While there are adult murres regularly present on three of the rocks at Yaquina Head, eagle disturbances have kept many of the adults from comfortably being able to incubate eggs. A juvenile and adult bald eagle regularly fly down towards the rocks, causing murres to “abandon ship”. This leaves many eggs vulnerable to predators. This behavior from the murres is called flushing, and is characterized by the murres flying off the rocks to raft in the water in droves in order to escape predators. Unfortunately, this leaves their eggs open to predation by the opportunistic gulls!
In recent years, we’ve noticed that eagle disturbance decreases as the summer goes on, and eagles have been observed only infrequently since the start of July. A small spree of murre egg-laying followed in early July yet these eggs were all lost within a few weeks to predators. Although murres are attending the colony more often now, we have not had new eggs in our plots since July 18th. Although at least one murre chick has hatched in an obscure crack at the base of Whale Rock – well sheltered from aerial predators – eggs elsewhere at Yaquina Head have all been predated. However, the continued presence of murres at the colony suggests that the possibility of breeding cannot yet be ruled out (Figure 2).
While there may not be any chicks in our Yaquina Head plots, murre chicks have been sighted at Depoe Bay since July 9th. This is good news! The chicks have survived at high rates and we expect the first of them to fledge by the end of the month. We have also started our diet observations for murre chick diets and have since observed smelts, flatfishes, and sand lance being delivered to chicks at Depoe Bay.
Figure 2. Some of the murres in this image from Yaquina Head are exhibiting behavior that corresponds to sitting on top of an egg. Leaning forward with their wings cocked out a little, murres spend a lot of time on top of their eggs, due to the fact that they have no nests whatsoever.
Earlier in the season, we thought that Pelagic Cormorants wouldn’t be breeding this year, and only a single active Pelagic cormorant nest was observed at the start of June. However, a small group of them have begun nesting at Yaquina Head’s Whale Rock since July 3rd, with the number of nests increasing since then. We are now following 15 Pelagic Cormorant nests at Yaquina Head and 20 nests at Depoe Bay, where nesting was also initiated extremely late. The lone nest from June now has two, three week old chicks and the numerous late nests ought to be hatching soon.
While murres and Pelagic Cormorants may have been initially having a little trouble, many of the Brandt’s Cormorants have been very productive over the last few weeks. Brandt’s Cormorants chicks began hatching June 16th (Yaquina Head) and July 2nd (Depoe Bay). The earliest chicks are already starting to get too large to fit in their nests, with some chicks at Yaquina Head considered to be fully fledged (> 25 days of age). It looks like it will be another successful year for Brandt’s Cormorants on the central Oregon Coast.
Western Gulls are also doing well at both Yaquina Head and Depoe Bay, with many of the chicks already becoming much too active to keep a close eye on. The chicks have been getting very adventurous (Figure 3), with some getting a bit too mobile to continue monitoring. We followed 23 gull nests in total at Depoe Bay, 52% of which succeeded in hatching chicks. We followed 9 gull nests at Yaquina Head, where 67% of them hatched chicks.
Figure 3. Western Gull chicks at Depoe Bay, spotted to be camouflaged with the rock surrounding them!
As for other seabirds, there’ve been a few Black Oystercatchers at both sites, and while their nests aren’t visible this year, I’ve been seeing them poke their heads out every now and again, especially around Depoe Bay. There have also been Caspian Terns seen flying overhead at Yaquina Bay. Both the terns and oystercatchers will be heard before they are seen in most cases, so make sure to keep an ear out for their calls.
Finally, in other very exciting news, we’ve also spotted a few Tufted Puffins flying around Yaquina Head (Figure 4)! Our last sighting was July 8th– which, coincidentally, is around the same time as the last sighting of tufted puffins at Yaquina Head last year, with 2023’s last tufted puffin sighting being July 9th. Their presence at Yaquina Head doesn’t necessarily mean they’re nesting there this year, though, as the puffins have not been seen bringing food back to nests at any of the surrounding rocks. But it’s still exciting to see them around the area.
Figure 4. Tufted puffin in flight. There are no signs that tufted puffins are breeding at Yaquina Head this year, even if they have been sighted there repeatedly.
Overall, while things may have seemed rather worrisome at the beginning of the season, there is some hope now that there will be Pelagic Cormorant chicks and (perhaps) a few murre chicks at Yaquina Head. The situation appears to be rosier at Depoe Bay, with an abundance of murre, cormorant, and gull chicks at that colony. Overall – between our breeding seabirds and visiting Caspian Terns and Tufted Puffins – it’s shaping up to be a pretty eventful season for seabirds along the Oregon Coast at Yaquina Head and Depoe Bay.
