Time: 4:30 pm
Date: March 14, 2018
Location: Island Isabela, Galápagos Islands, Ecuador
Weather: Hot, humid
Habitat: Ranges from mangrove forest to arid
I spent my spring break traveling in the Galápagos Islands. The Galápagos Islands (and most of mainland Ecuador) have little to no seasonality, rather tumultuous microclimates. Therefore the "winter" there looks much different than it does here in Vermont, but the birds that live there certainly have many adaptations for the unique environments they live in.
One commonality was many of the birds were considerably large (e.g. Brown Pelicans, Frigatebirds). I would attribute this to the generally hot and humid climate. These birds can have a lower surface-area-to-volume ratio than birds in colder climates because they don't need to retain as much heat. Perhaps some of the seabirds have counter-current exchange in their feet to cope with the cold ocean water.
Most of the birds I observed were either feeding or looking for food. For example, every time I observed a Striated Heron it was extremely focused on the water looking for fish to eat. I think this is because predation on birds on the Galápagos is relatively low, so birds don't have to worry about being preyed on and can worry more about eating.
The herons I observed as well as the Brown Pelicans, Frigatebirds, and Blue-footed Boobies were mostly hunting for fish. Most of the other birds were eating vegetation. The American Flamingo was particularly interesting to watch feed as it drags its curved beak along the waterbed then uses its lamellae to filter food out.
As aforementioned, there are no distinct seasons on the Galápagos. However, the area is significantly affected by El Niño and La Niña events which in turn impacts what birds eat. During El Niño, booby nests can become submerged by rising sea levels and chicks have died of starvation because parents were unable to find food.
Different species of birds overnighted in many different areas. Mangroves are prevalent on the Galápagos which were often taken advantage of by many birds. They could often be seen peppered with sleeping Brown Pelicans at night. Many of the finches nested in cacti.
Mini Activity- Snags provide important wildlife habitat for birds, small mammals, amphibians, and much more. Some examples of northeastern species that rely on snags would be Raccoons, Wood Ducks, and Red Squirrels. I did not observe any snags in the Galápagos. Most of the forests are mangroves and outside of those there are cacti. While there were no holes in the cacti, several finches were nesting on them.
2 males and 1 female observed
This picture depicts a male. This is clear because of its white head. Females have brown heads.
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