Wednesday, June 3, 2015

Hungry birds

The exposed mudflats, mangroves and beaches of the Upper Bay of Panama are a very important feeding station for both migrant and resident waterbirds and waders year-round.  The simply amazing numbers of peeps and other shorebirds that spent most of their lives here are prove of that.  But this time, I want to highlight that almost during every visit I witness a waterbird catching/eating large catfishes... like this Great Egret in Costa del Este.
Great Egret
The habitat is just ideal for the catfishes, so I guess they abound and are quite easy to catch. Sometimes, the birds just take them from the mud... or, in the case of the Magnificent Frigatebirds, are stolen from other birds.  This is a repetitive scene in Panama Viejo (where I took the next photos): a lucky bird catch a fish just to be harassed by these feathered pirates... and who can resist those bandits?
Magnificent Frigatebird
The Magnificent Frigatebird is a specialized kleptoparasite... parasiting by theft.  However, as it usually happens, this frigatebird was not the only one patrolling the site and soon another individual tried to steal the prize.
Two Magnificent Frigatebirds after the fish
Seeing those two frigatebirds in the air is fun.  The large birds are extremely agile in the air, and elegant... even when they chase each other.
Agility in the air
Eventually, the catfich fell to the floor... after all, nobody knows to whom is working... the birds spend 10 minutes disputing the catfish just to give it to a cat that was just passing by.
What can I say?  Some are luckier than others!

Monday, June 1, 2015

Bird of the Month: White-rumped Sandpiper

The White-rumped Sandpiper (Calidris fuscicollis) is a small to medium-sized shorebird, one of the largest peep species, that occurs rarely in Panama during its fantastic migrations.  Think about it... a bird that barely reach a length of 7 inches, a weight of 2 ounces and that breeds in Artic Canada and Alaska flies 15,000 km every year TWICE to and from its wintering grounds in Tierra del Fuego.
White-rumped Sandpiper
After leaving their breeding grounds, these birds fly out above the Atlantic Ocean to northern South America, where they start a trans-Amazonian journey to their wintering grounds.  During the northbound passage, they reach central North America via the Caribbean.  That's why they are so rare in Panama, which is not on their usual migration route.
White-rumped Sandpiper
The slender profile is due to the elongated wings, an adaptation to their long-distance migrations.  The slightly larger size and longer legs compared to other peeps sandpipers make them easily spottable  when mixed with other species while feeding or resting.
Short-billed Dowitcher, Semipalmated and White-rumped Sandpipers
Among the peeps, it is the only one with white upper tail coverts (the "rump"... in fact, it is dark-rumped), a field mark mostly visible when the birds flies, but sometimes while feeding or preening.  Is particularly useful if you inspect a tight flock of peeps in flight.
White-rumped Sandpiper flying
For these, and many other reasons is why we chose the White-rumped Sandpiper as our Bird of the Month!As I mentioned earlier, it is a rare transient migrant throughout Panama, always in small numbers.  It has been recorded in both coasts along the Canal Area and western Bocas del Toro.  During this last spring passage, it was recorded in the Pacific side of the Panama Canal (where I took all these photos) and Bocas del Toro... a remarkable set of reports for this species in Panama (we saw at least 15 different individuals in one site).
At least five White-rumped Sandpipers in this shot
For these, and many other reasons is why we chose the White-rumped Sandpiper as our Bird of the Month!
White-rumped Sandpipers
Literature consulted:
1.  Ridgely R, Gwynne J. A Guide to the Birds of Panama. Princeton University Pres 1989.
2.  Angehr G, Dean R.  The Birds of Panama. A Field Guide. Zona Tropical 2010
3.  The Cornell Lab of Ornithology All About Birds.  At