This was a slow posting week, but there should be more next week.
Tuesday: More Bad News for Wilson Bridge Eagles
Wednesday: Migrating Birds Nap Frequently
Thursday: Blackwater Resort Partially Blocked
Friday: Loose Feathers #69
This was a slow posting week, but there should be more next week.
Tuesday: More Bad News for Wilson Bridge Eagles
Wednesday: Migrating Birds Nap Frequently
Thursday: Blackwater Resort Partially Blocked
Friday: Loose Feathers #69
News and links about birds, birding, and the environment, plus a few other things.
The Maryland state Critical Area Commission has blocked the development of 313 acres of the proposed development near Blackwater National Wildlife Refuge in Cambridge, Maryland. The project would have built 2,700 homes, a convention center, retail complex, and a golf course on 1,080 acres of land adjacent to the Little Blackwater River. This river flows through the National Wildlife Refuge and eventually empties into the Chesapeake Bay. Runoff from the site could affect the resources of both. The 313 acres blocked by the commission would have held the golf course and retail complex. The developer could still build on the rest of the land, but any revised project would need to go through the local approval process again.
A five-member panel from the Critical Area Commission held hearings on the project and made a recommendation to the full commission. You can read the report here (pdf). The report sets forth the panel's concerns point-by-point and advises rejection. The main objections stem from a lack of data to support the developer's claims regarding impact on pollution, and noncompliance with watershed regulations. The commission's hearings were attended by over 100 people, and the commission received over 4,000 emails on the subject. Most responders opposed the project.
During migration, birds must travel long distances between their breeding and wintering grounds. The journeys frequently are thousands of miles from start to finish, and some birds may travel over 1,000 miles in nonstop flights. Some species travel during the day. Hawks, for example, glide from one thermal or updraft to another as they make their journey; these flying conditions are strongest during the day. Most birds, including songbirds and shorebirds, use more direct, powered flight. For such flights, the best conditions are at night, when heat is less intense and winds are weaker.
For this reason, many birds need to reverse their sleeping patterns during spring and fall. Instead of sleeping through the night and staying active during the day, they need to fly all night and then rest for the next flight during the day. Unfortunately migrating birds also need to eat, so the entire day cannot be spent sleeping.
It appears the solution is to take a series of cat naps during the course of a day. A study of caged Swainson's thrushes showed that sleeping patterns change during spring and autumn.
To find out how the birds get through these tiresome periods, scientists observed caged thrushes for an entire year, recording when and how long they slept. They found that during autumn and spring, when the birds are normally migrating, they reverse their typical sleep patterns, staying awake at night and resting during day.(Thanks to squeakysoul for the tip.)
But instead of sleeping for long stretches at a time, the birds took several naps a day, each one lasting only 9 seconds on average.
The thrushes also mixed up their shut-eye sessions with two other forms of sleep. In one, called unilateral eye closure, or UEC, the birds rested one eye and one half of their brains while their other eye and brain hemisphere remained open and active, keeping them semi-alert to danger.
The birds also occasionally slipped into another state, one that any college student who has ever been stuck in a boring lecture can relate to. Called drowsiness, this state is characterized by a partial shutting of both eyes that still allows for some visual processing.
A pair of bald eagles, nicknamed Martha and George, have nested near the Maryland side of the Wilson Bridge for several years. Despite the noise from heavy traffic and construction of a new bridge for the Beltway, they have maintained their nest and raised several chicks. Earlier in the year, Martha was severely injured in a fight with another female. As a result, she was taken to Delaware for rehabilitation, and her chicks died despite George's efforts to keep them alive. (See background here, here, here, here, and here.)
Martha is injured again, and this time her outlook is not as good.
It sounds like she may be spending the rest of her life in a wildlife rehab center. Such centers provide care and a safe home for the birds, and educational opportunities for the rest of us. Still it is sad to see wild birds unable to fly again, especially birds with the fierce wildness of raptors.Baker said it was unknown whether the beloved Martha, whose story captured the nation's attention in the spring, will survive her latest setback. She suffered a dislocated elbow, a grave injury for an eagle.
"The wing injury is pretty serious stuff," said Glenn Therres, eagle biologist for Maryland's Department of Natural Resources. "It's not like a broken leg, like you can put it in a cast and it will heal up." Therres guessed that she flew into a power line or tree branch during a recent storm.
She has been taken back to the Tri-State Bird Rescue and Research center in Delaware, where she recuperated from her other injuries this year. Specialists are deciding whether to send her to a special facility in Minnesota for surgery or to wrap the wing and hope it heals, Baker said.