Bird of the Week April 19: Double-crested Cormorant

Double-crested cormorants are found on clear open waters such as rivers and ponds to estuaries and oceans. It is the most widespread and common cormorant in North America.

These guys feed primarily on fish, and they can dive up to 100 ft. after their prey using their feet for propulsion. They can stay below water for 30-70 seconds. They will also eat crustaceans and amphibians. Unlike the anhinga that spears its prey, these guys grab prey in their bills.

Double-crested cormorants are monogamous and form large breeding colonies. The nests are large flat nests usually made from sticks and moss that is then covered with excreta. The nests are built anywhere from 10 to 40 ft up in the air in trees. Inland they will use cypress trees but coastal colonies typically use mangroves. both sexes incubate the nests for 28-30 days and the young remain with the nest for the next 21-28 days. Their numbers decreased substantially in the late 19th and early 20th centuries because of human persecution. However now this species is expanding their range and their numbers are increasing. Conflicts with humans arise because of this increase in numbers, and some people believe they are play a part in some fisheries collapses, but the evidence to support these claims are meager. Recently their has been proposed legislation to control their numbers because they will eat fish from fish farms. 

Bird of the week April 12: Limpkin

The secretive limpkin is a favorite of mine. I feel so lucky to see them along the flow-way at Panther Island with relative frequency. Found in wooded and brushy swamps, sloughs, and marshes plus along rivers,streams, and lakes throughout Florida and up into southern Georgia, the limpkin is usually seen alone and twitching its tail while looking for prey along waters' edge. This bird has a unique bill that when closed has a gap just before the tip that allows it to be used like tweezers, and this adaptation allows them to forage on apple snails. They also eat freshwater mussels, worms, and insects.

Limpkins are monogamous, and the males are territorial and will engage other males in aggressive and ritualistic displays that include behaviors such as loud calling, charging and retreating. Both adults work to build a platform nest composed of sticks, leaves, moss and other vegetation and are built in a variety of locations. Both sexes then incubate the eggs. The precocial young are looked after by the parents but can swim, run, and walk once they bust out of their shells.

This species is also unique in it being the only member of its taxonomic family! And while they resemble ibises and herons in their general body form, they are actually more closely related to rails and cranes. The limpkin (which was named for its unusual gait) is listed in Florida as a species of special concern. Their population is relatively stable in Florida, but numerous threats abound such as wetland drainage and apple snail population declines. Thick mats of nonnative vegetation like water hyacinth prevent them from finding food. Large monocultures of cattails degrade the environment as well and can also limit access to food. At Panther Island, we work diligently to keep cattails in check and to eradicate nonnative vegetation.

Bird of the Week for April 5: Barred Owl

How cool are owls? One of my favorite birds is the barred owl. Every year, a couple of barred owls nests in a cypress dome that I can easily access. I love their "who-cooks-for-you, who-cooks-for-you-all" hoot! They are found in forested areas, including swamps all the way along the gradient to uplands. I often hear them calling during the day throughout the year.
Barred owls feed on small mammals, birds, frogs, snakes, lizards, fish, and more. hunting occurs primarily at night or dusk/dawn but are often active during the day. While sitting on a high perch, they scan the ground and listen for prey which they capture after a short flight/drop onto the ground.
They are monogamous, and it is believed that they pair for life!  Nests are often in cavities of deciduous tees (such as my pair) or they will use open nests made by hawks. The female will incubate the nest for 28-33 days.  Young stay in the nest for 42 days while being fed by both parents. The young hatch helpless, with closed eyes, and they are covered in white down.