Tracking Recovery of Channel Island Bald Eagles and Peregrine Falcons

Sibling eagle chicks from a nest on Santa Rosa Island after banding. (Peter Sharpe, Institute for Wildlife Studies)

Biologists from the Institute for Wildlife Studies (IWS) were monitoring the recovery of both Bald Eagles and Peregrine Falcons on the Channel Islands again this year. Both raptor populations are still showing good signs of recovery and by monitoring them closely we can see what natural population fluctuations look like.

Bald Eagle Nesting Recap

The Channel Island Bald Eagles had a challenging year with a total of 14 chicks fledging in 2014, which was slightly lower than the 16 fledgings in 2013. This was mostly apparent on Catalina Island where only 4 chicks fledged from 7 nests. The explanations for some of the nest failures on Catalina Island are likely not related to DDT contamination but to natural events. The West End nest pair had a new female this year and a new nesting pair was discovered at Empire Quarry. Both of these nests were not able to produce any chicks this year. It is common for first time breeding pairs to have a “learning curve” during the first couple of years. We expect both of these pairs to breed successfully soon! Also, another very well-established nest known as Twin Rocks likely failed this year because the female is 30 years old and her age may affect breeding success.

Some good news for Bald Eagles this season was the discovery of a nest on the U.S. Navy-owned San Clemente Island. After several years of speculation that a pair was breeding on the island, IWS biologists finally found the nest. This is the first Bald Eagle territory on San Clemente Island in over 50 years! It is unknown if the pair actually bred this year, but it is very encouraging to see the expansion of nesting territories to 5 of the 8 Channel Islands.

Learn more about Bald Eagle Restoration on the Channel Islands.

Peregrine Falcon Nesting Recap

Peregrine Falcon populations remained steady for 2014 with 48 territories discovered this year up from 45 last year. Biologists also counted 59 chicks that hatched and more than half of them were banded. Banding peregrines is challenging since these birds nest on cliff edges that are difficult to access. Below is a short video showing the lead biologist on this project, Dr. Peter Sharpe, climbing down to a peregrine nest on Santa Rosa Island.

Peregrine Falcons are definitely rebounding on the Channel Islands. The current population exceeds known historic levels and the productivity, or numbers of chicks hatching and surviving in each territory, as well as nest success is increasing. We also know that peregrines are nesting on all eight of the Channel Islands and new territories are being discovered each year.

Learn more about Peregrine Falcon Restoration on the Channel Islands.

Peregrine Falcon chick on the Channel Islands. (Institute for Wildlife Studies)

Future Monitoring

The Montrose Settlements Restoration Program (MSRP) has plans to continue monitoring Bald Eagles and Peregrine Falcons on the Channel Islands through the 2017 nesting season as outlined in our Phase 2 Restoration Plan. MSRP and our partners are encouraged by the continued recovery of these species on the Channel Islands and the future sustainability of these populations. We can now all experience the wonder and beauty of these majestic birds soaring over their ancestral homes once again.

 

 

 

 

 

-Gabrielle Dorr, MSRP Outreach Coordinator