Bald eagles, ospreys and other birds of prey were practically wiped out until the pesticide, dichlorodi-phenyltrichloroethane (DDT), was banned in the United States in 1972.

The insect-killing chemical was developed for use in agriculture in the late 1940's. No one knew at the time that the most widely-used pesticide, DDT, would ultimately create such a devastating effect on raptor species.

DDT was passed up through the food chain. Runoff from farms drained into local waters. Fish, the main prey of many raptors, picked up the chemical from aquatic plants and insects. Bald eagles, ospreys and other fish-eating raptors absorbed DDT into their tissues from the fish they consumed.

Birds of prey at the top of the food chain suffered from cancer and reproductive irregularities. Many died from the ingested DDT.

Bald eagles and other raptor species that consumed fish accumulated high concentrations of the pesticide in their fatty tissues. Females laid thin-shelled eggs.

When a female sat on the weakened eggs to begin incubation, the egg shells cracked under the mother bird's weight. Raptor reproduction was essentially brought to a halt in areas where the pesticide was used.

The news continues to be good, perhaps great, for bald eagles. With bald eagle numbers in Pennsylvania beginning to reach higher and higher, bald eagle populations are close to the numbers needed to remove them from the Keystone State's list of endangered species.

The Pennsylvania Game Commission (PGC) Bureau of Wildlife Management is recommending the bald eagle be upgraded from threatened to protected status statewide.

Biologist Doug Gross, head of the PGC Endangered and Nongame Birds section, addressed the Pennsylvania Board of Game Commissioners Aug. 12. He said the Pennsylvania bald eagles' remarkable comeback has reached a point where eagles can safely be removed the threatened species list.

Gross reported that as of Aug. 12, there were 266 confirmed nesting bald eagle pairs in the state this year. These figures represent a continuing upward trend of nesting eagles throughout Penn's Woods. And this count is not the final count. The number of nesting pairs could increase before year's end. Last year, researchers documented 237 nesting pairs across the state.

"This year marks just another high point in the spectacular and widespread recovery of bald eagles in Pennsylvania and it's clear that the definition of a threatened species no longer describes them accurately," Gross said.

According to Pennsylvania regulations, a threatened species is defined as one that, throughout its range in the Commonwealth, may become endangered in the foreseeable future. The Bureau of Wildlife Management's recommendation to delist the bald eagle as a state-threatened species is based on achieving goals in the state bald eagle management plan.

The plan states that bald eagles will be delisted as threatened species if they meet four criteria of goals during five straight years. There must be:

1. At least 150 active nests statewide;

2. Successful breeding pairs in at least 40 counties;

3. A success rate of at least 60 percent of the known nests; and

4. Productivity of at least 1.2 eaglets fledged per active nest.

Gross said three of the four criteria have already been met for a five-year span and that eagles in 2013 will exceed for a fifth straight year the requirement of nesting successfully in at least 40 counties.

Determining nest success is the biggest challenge in eagle monitoring. The agency welcomes public information about the success and productivity of nests.

Said Pennsylvania Game Commission Executive Director Carl G. Roe, "The proposal to delist comes in the 30th anniversary year of the agency's first efforts to restore bald-eagle populations statewide.

"When the Game Commission launched its restoration program in 1983, only three pairs of nesting eagles remained in the state all of them located in Crawford County in northwestern Pennsylvania along the Ohio border.

"At that time, eagle populations had been decimated by the effects of water pollution, persecution and compromised nest success caused by organochlorine pesticides such as DDT. Three decades later, Pennsylvania's booming bald-eagle population represents one of the great success stories in wildlife conservation history."

The proposal to delist will be made to the Board of Game Commissioners at the board's meeting in September. The board can choose to vote on the proposal at a subsequent meeting. This is expected to provide the public an opportunity to comment on the proposal, Gross said.

"It seems that each passing year writes a new chapter in the story of the bald eagle's success in Pennsylvania and the latest numbers, and the recommendation to delist the eagle as a state-threatened species is the best news yet," Roe said.

"But the story isn't over. Pennsylvania has plenty of good bald-eagle habitat that's not currently being used by eagles. And as the years roll on, I'm sure eagles will give us plenty more to celebrate."

Gross said removing bald eagles from the state-threatened species list would neither hinder eagle populations in Pennsylvania nor knock off course the species' comeback here.

If the bald eagle is delisted, the bird will continue to be protected under the federal Bald and Golden Eagle Protection Act (the Eagle Act), the Migratory Bird Treaty Act, and the Lacey Act.

Under the Eagle Act, those who harm or disturb eagles are subject to a civil penalty of up to one year in jail or a $5,000 fine for their first offense. Criminal convictions can result in fines as high as $250,000.

"We will not be abandoning the bald eagle, but giving it less emphasis as we turn to new challenges in bird conservation in the state," Gross said.

That's the way I see it!

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