Bald E Biologists have tracked 15 breeding pairs of bald eagles on the Channel Islands, a record number since the species was nearly wiped out due to pesticide exposure.

Bald eagles make a comeback on the Channel Islands

By Chuck Graham 04/19/2012

When native species on islands are rescued, they’re prime examples of what can be accomplished in conservation. Because island species are so concentrated, once an invasive species is removed and human impacts are minimized, the results can be astounding in a short period of time.


Take into account the bald eagle recovery project on the Channel Islands National Park. The majestic raptors had been extinct across the chain for more than 50 years due to DDT (dichlorodiphenyltrichloroethane) poisoning, but following five years of aggressive reintroductions by the National Park Service, The Nature Conservancy and the Institute for Wildlife Studies from 2002 to 2006, bald eagles are now replenishing the volcanic archipelago, breeding, hatching and raising chicks on their own.


Bald eagle restoration efforts on the Channel Islands are funded by the Montrose Settlements Restoration Program (MSRP), a multi-agency program funded by court settlements and dedicated to restoring natural resources harmed by DDTs and PCBs (polychlorinated biphenyl) released into the environment by Montrose Chemical Corporation and other industrial sources in southern California.


“There’s been a lot of change in terms of bald eagles on the Channel Islands,” said Yvonne Menard, chief of interpretation for the Channel Islands National Park, “from hatchlings in the wild, and bald eagles leaving, then returning from the mainland and flyovers from Catalina”

 

Earliest known record of bald eagle hatchling on the Channel Islands

The 2012 bald eagle breeding season is kicking off a record-setting start with the earliest known natural hatching of a bald eagle chick on the Channel Islands. This early arrival was witnessed in early March at a nest near Carl Peak on Santa Cruz Island.


There are a record number of 15 breeding pairs active on the Channel Islands this year, with the number likely to increase as the nesting season progresses. Moreover, there are between 60 and 70 resident bald eagles — a sizeable number since their disappearance from the Channel Islands in the early 1960s. The significant jump in numbers over the last couple of years is due to more chicks hatching in the wild without human intervention and more bald eagles flying up from Catalina Island and across the channel from the mainland.


So far this breeding season, there are six known active nests on Santa Cruz Island, including one with a hatched chick and three other nests with eggs. On Santa Rosa Island, there are two nests, both with eggs. There is one nest on West Anacapa Island in the same area where, last year, a bald eagle chick hatched for the first time since 1949 on the tiny islet.


The famed Pelican Harbor pair on the north side of Santa Cruz Island that, in 2006, naturally hatched the first bald eagle chick on the Channel Islands in more than 50 years once again kept everyone guessing. Biologists moved the webcam several times to follow the nesting pair before the birds finally settled on a site near Chinese Harbor on Santa Cruz Island. The female laid her first egg on March 5.


“Biologists did a lot of scrambling in the hopes of setting up the webcam,” continued Menard.  “We jumped the gun thinking the nest would be at Twin Harbors, but the pair changed their minds and moved back to Chinese Harbor.”


The Pelican Harbor pair’s first offspring in 2006, a female known as A-49, has been seen with a mate nesting near the west end of Santa Cruz Island. If A-49 successfully hatches her eggs this year, another milestone will be set with a second generation of naturally hatched eagles.

 

History of recovery

Prior to 2006, the last-known successful nesting of a bald eagle pair on the northern Channel Islands was in 1950 on Santa Rosa Island. Bald eagles disappeared from the Channel Islands by the early 1960s due to human impacts, primarily DDT contamination. The effects of these chemicals are magnified in the pelagic food web, causing bald eagles to lay thin-shelled eggs that either dehydrate or break in the nest.

To watch these majestic birds daily during the breeding season, visit the Channel Islands Live Bald Eagle webcams on Santa Cruz Island at: www.nps.gov/chis/photosmultimedia/bald-eagle-webcam.htm.

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