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.

1st week of banding completed

This week we finished our first full week of banding here in Tortuguero. We have 5 banding sites, including our home site at Caribbean Conservation Cooperation (CCC) which we band every other day. CCC has 20 nets which we aim to open at 5:40, before the sun rises just as the first rays of light are penetrating the rainforest. The timing can be tricky, as we learned this week when we found ourselves extracting bats not birds from a net opened too early. Our home site consists of 5 nets arranged in the coastal scrub habitat, and 15 nets in the adjacent highly disturbed secondary forest. So far our most captured birds at CCC seem to be residents such as White Collared Manakin (my first bird banded in Costa Rica), Variable Seedeaters, and 3 common hummingbirds - Long-tailed Hermit, Bronzy Hermit and Rufous-tailed hummingbird. There are also some migrants hanging around, Prothonotary Warbler being the most common capture, but we also have duplicate catches of Chestnut-sided Warbler, House Wren, and Yellow-throated Vireo. Baltimore Orioles and Yellow Warblers also seem to be abundant, but we have yet to catch one.





A migrant female Prothonotary Warbler (above). The sex of these birds can be reliably determined based on the amount of white on the tail feathers (below). The males will have white in all tail feathers whereas in the females it will be lacking or barely visible in the inner tail feathers.




A Chestnut-sided Warbler, common throughout Costa Rica during the winter months. This, the first CSWA we caught, was already banded indicating that it had successfully migrated to North American last spring and returned to winter again in Tortuguero selecting the same exact area to winter as last year!!



White-collared Manakin (female above, male below). The males preform complex dances in leks in hopes up attracting a mate in which they produce a loud snapping sound with their wings. The snapping sound is a constant early morning occurrence however I have yet to find a dancing bird. Video of manakin dance




We also have a banding site located in the Parque National de Tortuguero. This expansive park was founded in 1975 to protect the important nesting grounds on the beaches for sea turtles as well as the surrounding rainforest. Banding here involves an early morning hike of about 25 minutes to the park where we set up our nets. Consisting of mostly primary rainforest we see (and hear) a totally different array of birds than at CCC. This place is a paradise for birders and the mornings are filled with bird songs such as the beautiful Song Wren (3rd link) Song Wren Song We spotted a White-Crowned Pigeon in the coastal scrub and unknown to me, this is an extremely rare sighting for Costa Rica. Upon entering it in ebird I received a confirmation email asking for more clarification. Luckily I snapped a terrible, documentation quality photo which I submitted and word got around in the birding community initiating a steady flow of birders in the country into the park to search for it. My first Costa Rican rare bird!


Documentation photo of a White-Crowned Pigeon in Tortuguero National Park.


Tortuguero National Park is home to a spectacular amount of biodiversity including 375 species of birds, 400 species of tree and over 2000 species of plants. It is also known for its abundance of the dangerous eyelash viper (Bothriechis schlegelii). This beautiful but highly venomous snake is present in many color morphs. It certainly keeps me on my toes and adds a whole new element to banding birds. I make it a rule to not step or touch anything without looking carefully. We took great care when we set up the site to make our net lanes wide to provide ample space to walk by the nets without touching vegetation. I have so far seen 2 (both of the yellow phase) in just 3 trips to the park.



An Eyelash Viper (below possibly a juvenile based on its much smaller size)



Next week we will band 3 times at CCC as well as travelling to 3 sites (the Airport, Cano Palma - a Canadian run tropical research station in old growth primary rainforest, and Tortuga Lodge - a tourist lodge located within primary rainforest where pale-billed woodpeckers, a relative of the ivory-billed woodpecker, are sometimes caught. With any luck I will get to band one myself).

Tortuguero

A lot has happened since my last post. Spent a couple days in San Jose getting to know the common bird species. I was lucky enough to be able to visit INBIO, the Costa Rican equivalent of the Smithsonian. I got a private tour of the insect taxonomy lab and was blown away by what I saw. Picture a building the size of a high school gym, filled with specimens. One entire wing, bigger than my house, was dedicated solely for beetles and butterflies which are pinned in trays stacked 35 high 15 long and hundreds of rows. You do the math, millions is what you will find. Each tray has 10-100 insects depending on size, rhinocerous beetles, weevils, fireflies, click beetles, silver and gold beetles, blue, yellow, red, striped, poca dotted, zig zags, you name it. No pattern made by man has not already been displayed on a tropical beetle. This place turns out new species weekly, in fact it has been calculated that in their first 20 years (celebrated this year) they have described a new species every 3.5 days!!! There is also a little park on the grounds that has a impressive array of birds to be found. I saw some beautiful life birds such as RUFOUS CAPPED WARBLER, and NORTHERN JACANA as well as some familiar migrant birds such as YELLOW WARBLER and BALTIMORE ORIOLE.

On Monday, we left for Tortuguero, this involves a 2.5 hour bus ride to Cariari through the perfectly preserved primary rainforest of Braulio Carrillo National Park. The bus rides up over the mountains offering breathtaking vistas of steep precipices blanked in rainforest without a human blemish as far as one can observe. From Cariari we took the bus 1 hour to Las Pavonas and transfered to a boat which took us to Tortuguero an hour further. Tortuguero is one of the wettest rainforests in the world with nearly 6000mm of rainfall each year. There are no roads and the only means of transport is boat which winds through the maze of canals that penetrate in every which direction. The town itself is situated on a narrow sliver of land between the caribbean and Tortuguero lagoon and at the opening of the massive Tortuguero National Park and this is where I am staying at a turtle investigation center.

This past week has consisted of the grueling job of opening the trails and banding net lanes reclaimed by the jungle from when banding last occured this time last year. The machete is the best tool assuming you don't slice though an eyelash pit viper of which I was very careful not to do. We were able to clear one site a day. I have found only one snake so far, a non venomous tree snake. I have seen lots of new birds including 3 species of trogon and 2 manakins as well as the absolutely stunning golden hooded tanager (you must google this bird).

Tomorrow we open the nets for the first time here at CCC. I wonder what the first bird will be.

A Whimbrel (Numenius phaeopus)feeding on Tortuguero Beach

Black-bellied Plover (Pluvialis squatarola)

Cane Toad (Bufo Marinus)

Bare-throated Tiger Heron (Tigrisoma mexicanum)

A very cool insect