You either love them or hate them. I'm talking about a bird that few have seen and even fewer know much about. It's the Black-Crowned Night Heron and it's common around Clear Lake.
For years one of the primary nesting and roosting areas for the heron was Library Park in Lakeport and herein lies the problem. The droppings from the birds were not only unsightly and nauseating but, in the past, have made much of the park unusable for local residents and tourists.
Actually, the Black-Crowned Night Heron is a fascinating bird. As the name implies it is primarily a night bird. Thousands of years ago the bird couldn't compete with other herons to feed during the daylight hours, so it evolved into a night feeder. Part of the evolution of this bird is its excellent night vision. Biologists say the bird can see as well at night as most other birds can in the daytime.
The primary food for the Night Heron is frogs, fish and other aquatic creatures. Because it is a wading bird it prefers shallow swamp-like lakes. Clear Lake, with its tule shores, offers ideal habitat for the Night Heron.
It is also considered a migratory bird under the U.S. Fish and Wildlife regulations and is protected. According to bird experts, many of the herons spend their entire life at Clear Lake, but others migrate in and out of the area.
The average height of a Black Crowned Night Heron is 23-26 inches, and it weighs about 21-25 ounces. A distinct feature of the heron during its breeding season are its long legs. Out of season the legs are green and during breeding season the legs and feet turn yellow or red.
They nest in colonies. The males provide the sticks and other debris for the nest and the female actually builds the nest. The coloration of the adults are a glossy black crown and back, with the rest of the body being gray with white underparts.
The Black-Crowned Night Heron starts its breading season in March. The female lays 3-5 pale bluish-green eggs and both male and female incubate the eggs. The eggs hatch in 24-26 days. The young herons can fly at 42 days.
Both parents provide food for the young by regurgitating fish, frogs and insects into the nest. Because of this fish diet, the droppings are often smelly. The birds also drop semi-digested fish parts to the ground. That's what happened at Library Park. Because it's a night feeder the herons spend the day in the treetops on the nest, tending their young. This is also the time when the park draws most of the people. Having a picnic under a tree that contains several heron nests can be quite an experience.
Even after the breeding season ends in May, the herons will still use the trees as roost trees the rest of the year.
Experts say that short of cutting down the nesting trees, it's nearly impossible to get rid of the herons at the park. Even if you destroy the nests, they will just build new ones. Actually, the City of Lakeport created a computer model of the heron warning signal. It is the alarm to herons to vacate the area and appears to be working. Most of the herons nest in the trees at Willow Point and not in the park itself.
Because it is classed as a migratory bird, it is also against the law, both federal and state, to destroy a nest that have eggs or young birds.
As long as the food supply stays plentiful, there will probably be an increase of Black Night Herons in the park in the future. These are colony birds and if you have one you will end up with a dozen. That's their nature. The answer to this dilemma is to not sit below the large trees in the park and certainly not to have a picnic under these trees.
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