Quick Action Ensures Survival of Poisoned Eagles

Bald eagle rescued, rehabilitated and released with satellite transmitter to track movements

by Kathy Clark, Endangered & Nongame Species Program, NJ Division of Fish & Wildlife

On Sunday, April 15^th, I got a call that three bald eagles were spotted in a farm field. Not too unusual in rural Salem County, but this good neighbor was rightly concerned that something was wrong.  Pedricktown resident Steve Wilson approached the eagles and not only did they not fly away from him, but two could barely sit upright and a third was stumbling away.  Steve made phone calls and, at 7:30 at night, couldn’t reach any of the wildlife centers or offices.  Persisting, he made a connection with Dr. Erica Miller, a wildlife veterinarian who for over 20 years was both clinician and surgeon at Tri-State Bird Rescue & Research in Newark, Delaware.  Erica is also a long-time partner on the NJ Bald Eagle Project, and called me about 7:45 that evening.

We have a strong network of people in NJ who care about eagles and many are willing to drop everything to help with a rescue.  After I spoke with Steve, the neighbor who found the eagles, my next call was to John Fox.  John lives in Salem County and in addition to volunteering for the Eagle Project, he took training on how to rescue wild birds in trouble.  That evening, with dark fast approaching, John needed only an address and he was “on it.”

The circumstances required fast action:  Steve noted that the three eagles were near a dead red fox, and suspected the fox was poisoned and the eagles were suffering secondary effects after scavenging the carcass.  Located in Delaware, Erica was already figuring out a response as well.  Once we knew John was enroute to try to capture the eagles, Erica alerted the staff at Tri-State, and asked them to draw up doses of atropine, effectively an antidote to the types of poison used to kill “nuisance” animals like foxes, and to prepare to accept the birds that night. She stopped at Tri-State to get the atropine, and headed to meet John along the way to begin immediate treatment for secondary poisoning.  By the time John arrived it was getting dark.  Steve headed out into the field with John, and at first they had trouble finding the birds.  They soon found them and had two of them captured by the time Erica arrived on site.  The third bird was still weakly flighted, but they managed to keep it in their flashlight view as it glided low across the field and over a creek, landing awkwardly on a low branch of a tree. Working together, they got the bird out of the tree and captured it as it again attempted to take flight.

These young bald eagles – their plumage identifying them as 2, 3 and 4 years old, respectively, received the best care possible that night.    Erica administered the atropine to each bird before they were installed in pet carriers for transport, and they each responded positively, becoming more alert during the short drive to Delaware.  By 11 PM, they were resting in the wildlife hospital at Tri-State. With luck, they’d recover.

The following day the veterinary team at Tri-State evaluated each eagle.  One, the youngest, had bounced back; he may have taken the fewest bites of the poisoned carcass and that worked in his favor.  He was ready for release just two days after the incident.  Standard blood tests on the other two eagles showed slightly elevated lead levels, which is not uncommon in birds that scavenge and can pick up tiny shotgun pellet fragments in deer that die during and after hunting season.  Tri-State staff began treatment to help the birds shed the extra lead; called chelation therapy, the treatment binds lead and helps expel it from the body.  They also sedated the two birds and pumped their stomachs to remove the traces of lead seen on the birds’ x-rays. After just a couple of days, though, the three year old eagle took a turn for the worse and died overnight.  It was a sad setback.

The remaining eagle, the four year old with a mostly-white head just one year away from the full white head of adulthood, was watched carefully.  He was not gaining weight as expected, and we didn’t know if he’d actually pull through.  His release would be put off until he gained some weight and got his strength back.  Eagles face plenty of obstacles during every day survival; he needed to show us he was ready for life in the wild.

Ten days after his rescue, Erica said he was looking stronger, and we should plan to release him within a few days.  On my office windowsill sat an unused satellite transmitter, one I’d had refurbished last year but hadn’t had the chance to field.  Until now, our satellite tags have been used on eagle nestlings, attached at the time of banding when they are just eight weeks old.  Trouble is, the survival rate of eagle nestlings is barely above 50 percent.  Young eagles have a lot to learn in order to survive their first year and their second.  A four year old eagle has beaten the odds, proved that he knows how to survive, and should soon be scoping out his own nest site.  This was our chance to follow the habits and habitats of a near-adult bald eagle.

I met Erica at Tri-State on Friday morning, and we set to work preparing the harness and readying the gear.  Erica easily netted the eagle in the large flight cage.  Once the hood was on his head, putting him in the dark, he was calm and showed no signs of stress.  It takes some time to attach a transmitter harness; it must fit perfectly – not too tight nor too loose – and we take the time required to be sure.  That done, we took some measurements and banded him with a USGS band and green NJ band engraved E/62.  We returned him to the flight cage where he quickly gained a high perch, then flew across the enclosure far from us.  He flew well and regarded us from above.  We left him and, five minutes later, watched on the cage security cam as he ate the lunch left for him earlier.  He seemed to take no notice of the new transmitter on his back!  It seems like he was indeed the perfect patient.

On Sunday, April 29^th, two weeks after he nearly died from a poisoned meal, bald eagle E/62 was released from the field behind Tri-State in Delaware.  Nicknamed “Pedro” (for his “hometown” of Pedricktown), he flew beautifully back into the wild. About one day after release, he had crossed the Delaware River, back into Salem County, back home.

• Make a donation to support our Bald Eagle Monitoring Project
• Track Pedro on the New Jersey EagleTrax website:  http://www.conservewildlifenj.org/protecting/eagle-trax/