10 October, 2013

Island Girl Arrives on the Mainland in Mexico

Island Girl left her "ship" roost on Tuesday morning and continued to fly south towards the coast to complete her crossing of the Gulf. Once again, just like last year, she crossed this huge body of salt water at its widest possible point, covering the maximum distance across the Gulf.

Why does she do this? Why does she subject herself to such danger? Why not take the presumably safer coastal route or cross through Florida as before? Why not minimize her over-water exposure?

We don't know the answers to these questions as yet. But we learn more of what she does and is capable of doing with each and every migration she completes.

So, after flying another 406 km (252 miles) across the water, she safely made landfall on the coast just to the east of Lake Catemaco, one of the most beautiful places I have seen in Mexico. Many of you FRG members have been there on some of our hawk tours awhile back.

She was about 150 km south of Veracruz, the site of the largest known fall hawk migration in the world. So from here on, she will be traveling with thousands of other raptors of many species all the way through Mexico and Central America.

She roosted on the coastal plain about 3.1 km (2 miles) inland from the beach. She selected a small group of trees in a mixed farm field/forest habitat at 600' elevation.

This slope leads up to the famous Sierra De Santa Martha, in the Tuxtlas of tropical Mexico. Some have told me that this is the farthest north you will find true tropical rain forest in Mexico.

There was also talk of this area being the northernmost known range of the Harpy Eagle in Mexico although they do not seem to be there anymore. There are White Hawks, King Vultures, and Common Black Hawks here, all typical of the tropics.

Definitely tropical habitat now.

She slept roughly 26 miles north of the coastal town of Coatzacoalcos, where she roosted last year. So her route and landfall point was almost identical this time.

However, in 2012 she arrived there on Day 12 of her migration. This year, she arrived on Day 20, so she is taking her time this year.

I like to think that there is really no reason for her to rush south. She has no breeding territory to defend in Chile. And the longer she takes to move through her migration route, the more she learns about it. I believe that this gives her an advantage by gaining familiarity with her path and the food available all along it.

Many years ago, I used to think that the idea was for all peregrines to migrate south as soon as possible to acquire the best winter territories well before any other falcons arrived. I still think that is true for some birds in some locations.

However, these "deep" peregrines,the ones that have so far to go, are a bit different. They can be "slow migrants", some not arriving on their southern ranges in Chile and Argentina until mid -December.

Island Girl is one of these "deep" peregrines, making one of the longest peregrine migrations in the world.

And think of all the knowledge she has acquired during these many passages.

Adult peregrines or "haggards" just keep on improving with age.


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