Beautiful Birds

So, I could talk about rain in all of my blogs. I could talk about the 11.7 inches that fell in 18 hours flooding half the town. (It is hard for this place to flood badly mainly because it is already flooded). I could talk about the 3 mile walk home from the airport banding site along the beach in drenching downpours, strong Carribean winds, amongst lightning bolts and falling coconuts; but I am not going to talk about rain. Instead I am going to talk about cool birds. Like this Royal Flycatcher that we caught at Cano Palmas Tropical Research Center. This amazing bird rarely displays its spectacular crest unless courting or agitated. Banding sessions are a great way to see the crest because the bird leaves it open constantly in defense. This bird is rare in the Carribbean, but has been caught in the past by the banding teams here. Last one was in 2008. This is a bird that I actually banded in Peru in 2004 and depending on some sources they list it as a different species meaning that I have banded 2 different species of Royal Flycatchers!










Another amazing bird that I am going to talk about is this Red-capped Manakin. Like the white collared manakin that we catch very frequently and other manakins, the males preform spectacular courtship dances in hopes of wooing an available female. This bird's dance is so elaborate it has earned the nickname the "moonwalking bird" because of its slide dance that it preforms. MOONWALK VIDEO





We also band hummingbirds. Here in Costa Rica there is an astounding diversity of hummingbirds. My guide book lists 57 species! Compared to the one species on the east coast of the US the Ruby-throated Hummingbird (which incidently is a winter resident in Costa Rica) the skies are filled with tiny flying jewels. We have captured 6 species. This bird, the Rufous-tailed Hummingbird is our most frequently captured hummer.




The bands we use are very very tiny. They come in a pre printed sheet of aluminium which we then cut out, trim, shape, sand, and polish so that they are safe for the birds. This bird we captured early in the season, a Long-billed Hermit (below), was already banded. Since no banding has occured since last winter, we know that this bird has survived here for at least a year. Pretty impressive given the numbers of hawks, kites, falcons, lizards, snakes, and other predators that would love to eat one of these.



Another Long-billed Hermit (below 2). This beautiful bird is large for a hummingbird, topping the scales at about 6 grams compared with the Ruby-throated Hummingbird at about 4 grams. In the extremes, Bee Hummingbirds of Cuba weigh only 2.2 grams while the largest hummingbird in the world, the Giant Hummingbird of South America, can weigh 20 grams (think song sparrow size).






Notes from the field:

Get ready all you northerners. (Which from here includes just about everyone). Migration is starting down here. Shorebirds are increasing in number especially Sanderlings which have arrived by the hundreds compared with the small numbers seen this winter. I heard a Yellow-throated Vireo, and winter resident here that is normally silent, sing its full song. We have also seen an increase in the number of new bands applied to Prothonotary Warblers. (We have been just catching the same 9 or 10 individuals over and over again but today we applied 3 new bands). Five times a day we conduct migration counts from the beach and note all birds moving north. As you can imaging this was pretty boring during the winter when we only occasionally saw Magnificent Frigatebirds, or Common Black Hawks that were probably just foraging rather than migrating. Things have changed. Purple Martins and Barn Swallows are now migrating in huge numbers with our counts reaching into the hundreds for the day. Cliff Swallows and bank Swallows are also on their way in lesser numbers. It is very interesting to see how migration begins. While the resident Mangrove Swallows and Gray-chested Martins continue their normal feeding, migratory swallows take on a whole new task. The impressive feat of migrating thousands of miles north to take advantage of the available food sources that come with spring in the US and Canada. Lets hope they make it. While Costa Rica is losing birds to northern forests for the summer, some birds also come here from South America. Yesterday, I spotted 2 Yellow-green Vireos just outside the banding station which surely have just arrived from wintering further south.

The Spectacular Blue-gray Tanager (above)

Mangrove Cuckoo

Black-cowled Oriole (note that one individual is banded, not me!)

It's a Jungle Out There

First off, Happy Valentine's day Eliza. I am missing you loads and can't wait till I see you again.



This past Friday afternoon while I was out checking the nets, my banding partner went to check on some bird commotion that was occuring in a tree nearby the banding station. To our surprise, we observed a Green Parrot Snake (Oxybelis fulgidus) that had caught a black-cheeked Woodpecker and was attempting to kill it with its venom. This snake is a specialist in eating small lizards and occasionally insects, birds, and small mammals such as mice. The Black-cheeked Woodpecker, extremely abundant in the Caribbean lowlands, seemed to be a very sizable prey for the snake whose neck seemed to have one tenth the girth of the medium sized woodpecker. (Similar in size to Red-bellied for those of you familiar with Eastern U.S. avifauna). It was quite an impressive feat to watch this small snake subdue the woodpecker and swallow it whole before retreating to a resting place out of site in the canopy of the tree. Numerous other birds such as yellow warbler, and Boat-billed Flycatcher participated in mobbing the snake and scolding it although they seemed to loose interest once the bird was diseased. Even though the bird was dead within 30 minutes, the whole ordeal took nearly 4 hours as the snake attempted to swallow it's prized catch. This is a snake I have handled in Peru, and if my memory serves me correctly it was quite feisty, and willing to bite, although the toxin is not harmful to humans barring an allergic reaction. What a beautiful snake. What an unfortunate woodpecker. I am happy to report that there still seems to be plenty of Blacked-cheeked Woodpeckers singing in the area.

A Yellow Warbler (Dendroica petechia) participates in mobbing the offending snake.

In other news, I was fortunate to be able to take the company kayak deep into the park and explore the extensive canal system. After an hour paddling against the flow I reached Harold Canal (formerly Death Canal, of which I was pleased that this former name had been dropped). This is one of the best wildlife experiences I have ever had. The canals are narrow, 20 feet across, giving the whole scene a surreal jungle book experience. The wildlife is top notch, with all 3 species of monkey, as well as sloths, very easy to observe. River otters are also abundant and I saw 4 including one who was happily gnawing on a fish unaware of my presence. The birdlife is some of the best I have ever witnessed. It will take me many more trips here to figure out what all the birds singing in the canopy are but notable life birds I saw include BLUE DACNIS, GREEN IBIS, SUNGREBE, GREAT CURRASOW, and the hightlight - GREAT GREEN MACAW, the seventh species of macaw I have seen in the wild and 22nd species of Psittacidae (the family that consists of parrots, parakeets, and macaws). The pair of Great Green Macaws, a species I was really hoping to see, flew right overhead after announcing their presence with a great raspy scream. They then banked towards the water surface and sharply to the left offering me detailed binocular views of their magnificient plumage before disappearing through the light drizzle into the hidden canopy in search of fruiting trees.

One of the neat things about banding is it gives us the opportunity to catch difficult to see ground foraging birds such as wrens and sparrows. Several times I have checked the nets only to find a bird I had not previously detected despite conducting intensive area searches. I am quickly learning to appreciate wrens of the family Troglodytidae for the unique challenge they offer in locating, their beautiful and complex songs and skulking behavior. As their scientific name implies (Trogodytidae = cave dweller) the often choose to forage in dark crevices and are small and hidden except for their complex songs. Having spent a month in Costa Rica, I have now seen 4 species including the super abundant migratory House Wren which most are probably familiar with. These wrens prove to be quite unlike the Carolina Wren that I am used to from the states in that they are very secretive and not often spotted. In fact of the 4 species, I have only seen 3 because the wound up in the mist net.

Above and below: Bay Wren (Thryothorus nigricapillus)

Below: White-breated Wood Wren (Henicorhina leucosticta)

Above and below: Song Wren (Cyphorhinus phaeocephalus)

A very interesting bird that we caught this week, and one of my favorites in Costa Rica, is the American Pygmy Kingfisher. This small kingfisher has all the traits of a kingfisher except that it weighs only 18 grams, roughly the size of a Prothonotary Warbler or a Song Sparrow. They occur in thick forest along streams and canals with dense vegetation such as mangroves searching for fish and tadpoles, and occasionally insects. This particular individual we captured flew into the net right next to me as I was extracting a large spiny stick that had become entangled in the net (yes we have to take out insects as well - weevils, dragonflies, grasshoppers, massively large stinging wasps and bees).

American Pygmy Kingfisher (Chloroceryle aenea) - the lack of a green breast band makes this a male bird.

We aged this bird SY (second year) due to the presence of a block of 3 older retained primaries. Visible in the bottom picture as the 7th, 8th, and 9th primary in from the tip.

A couple days later, we captured 2 more American Pygmy Kingfishers including this bird which had a strange deformed bill shaped much like it was a crossbill eating pine cone seeds rather than a kingfisher eating fish. It appeared to be an older bird due to its plumage details and we aged it at least AHY (after hatch year) since it had a fully ossified skull indicating that it is able to successfully hunt with its deformed bill.

Willets (Tringa semipalmata)on their wintering grounds

Tropical Kingbirds (Tyrannus melancholicus) Tortuguero, Costa Rica

Rain

This week was a soggy one. Tortuguero, Costa Rica, with an excess of 6000mm (19.7feet) a year, is one of the rainiest places on the planet and the rainiest in Costa Rica. The pattern seems to be that we get a late night storm, followed by and early dawn one. The next one usually comes after we have been dropped off from the boat into the middle of nowhere with no shelter to open the nets leaving us entirely soaked for the rest of the day. Banding during these days can be tough as we must close the nets when rain starts. With 15-20 nets and some of them with birds to be untangled, this can be a tricky maneuver. Luckily, tropical birds seem to be less affected by the rain than the northern species and certainly the risk of hypothermia is drastically reduced. Still we aim to have the nets emptied and closed when a storm comes in only to reopen them one hour to get rained on all over again. The incredibly high rainfall contributes to the amazing amount of diversity that can be found in Tortuguero such as this male Emerald Basilisk (Basiliscus plumifrons).



This along with Costa Rica's 2 other basilisk species are collectively know as the Jesus Christ Lizards because of their ability to walk on water when frightened. Another reptile found in Tortuguero is the Spectacled Caiman (Caiman crocodilus).



Caimen like to hide in the shore vegetation waiting for some passing, unsuspecting prey...



Possible this beautiful migrant Yellow-Crowned Night Heron (Nyctanassa violacea) will fall victim to the waiting Caiman


Or this locally common Northern Jacana (Jacana spinosa).





Or maybe this Anhinga (Anhinga anhinga).



Despite the rainy days that we encountered we still managed to catch a lot of cool birds. The highlight was catching 3 new birds including one lifer, the beautiful BAY WREN, a new migrant for me in Costa Rica a NORTHERN WATERTHRUSH, and the hard biting painful to handle BUFF-THROATED SALTATOR who let me know what he felt about his new band applied gently to his right leg. These were all captured at the Airport site, a 45 minute walk or 10 minute boat ride to the north after a morning of heavy rainfall.

Bay Wren (Thryothorus nigricapillus) captured in highly disturbed secondary forest near Tortuguero, Costa Rica

Northern Waterthrush (Seiurus noveboracensis), a Neotropical migrant which breeds in northern U.S. and Canada captured on its wintering grounds near Tortuguero.

Buff-throated Saltator (Saltator maximus), a relative of the Northern Cardinal near Tortuguero, Costa Rica.

Common Tody Flycatcher (Todirostrum cinereum) a commonly captured bird in Tortuguero. This is one of the smallest flycatchers I have ever seen, similar in size to a kinglet.

I just wanted to quickly revisit last week's post in which I talked of determining the sex of Prothonotary Warblers based on the amount of white in the under tail feathers as per Peter Pyle's Identification Guide to North American Birds used by banders. I didn't have a good photo of the male, but I got lucky this week and caught one. Notice how the male shows extensive white in all tail feathers whereas the female lacks white in some of the tail feathers.







These are some of the things that banders use to determine age and sex of birds in the hand. Some characteristics are obvious and easy to see such as white feathers in the tail whereas others are more subtle and take much more practice and experience such as recognizing molt limits or determining age based on feather wear. I learn a bit more with each bird I handle and have learned much from the various other banders I have worked with.

Finally, there have been several reports of a boa being seen at night by the night security man Don Victor. I told him "Victor, si U.D. ve a una culebra mas gruesa que el brazo, me tiene que despertar". If you see a snake thicker than your arm you must wake me. Sure enough I got a knock on my door at 11PM this past Tuesday night. Hiding in the vegetation by the lake shore was a Red-tailed Boa (Boa Constrictor), a long sought out snake by me that I had never been able to see in Peru. Here is a horrible photo of the snake at night. Next week we are off to the primary forest sites. Hopefully we continue to capture interesting species.