Updated Bird List – Fall 2017

I recently finished updating our Western Caribbean Slope bird list, based on the August 2017 Clements List. This last version shows some significant changes, such as, removing from the Thraupidae family the Rosy Thush-Tanager (Rhodinocichla rosea) and the Dusky-faced Tanager (Mitrospingus cassinii) and putting them in to their own family, Rhodinocichlidae and Mitrospingidae respectively.

As of this update, we have a total of 522 species on our list.  It is very likely that during the year this number will change, owing to Bocas del Toro’s outstanding diversity.

One of the additions to our bird list, is the Forster´s Tern (Sterna forsteri), a rare species for the country; only one bird was observed, resting with a group of Royal Terns (Thalasseus maximus), at the Changuinola River mouth, months ago. This species is easy to recognize in its winter plumage, by the black, coma type of shape, ear patch.

Birding Panama

©Brooke A. Miller

You can download the current Clements based bird list on our Birding page.

Tarpon Working Baitball

So, we received a drone for Christmas and have spent some time learning how to fly it and capture footage around the neighborhood over the past month after the end of high season.

Jay called back on the radio from the boat as he headed out to pick up guests recently telling Jim he needed to go check out the tarpon rolling around a large baitball near the lodge.  Fortunately for us the baitball was near the lodge for a few days.  Check out this footage of the tarpon, sting rays and snapper corralling the bait fish.  The change in shape of the baitball is all due to predators working the smaller bait fish.  Nature at its finest.

Bocas Shorts #4: Two-toed Sloth Commute

Sloth CommuteAfter its nap, the two-toed Sloth start crawling up higher, looking for branches that connected, and using the palm leaves to get to the power line.  At least that’s what we thought, that he was planning on going across the power line, because we have seen this species use the wire as a way to get access to to some of the trees where they feed near the main building or just to move from one patch of forest to another, but…

In the end the sloth had something different in mind.  He successfully accessed the power line and then went on to the next palm tree.  Why? We are not sure, but we chose to move away and let it make its way alone.  A few minutes later I went back to look for it and could not find it.

Frog v. Robot

Frog v. Robot

We invite scientists from the Bocas del Toro Research Station of the Smithsonian Tropical Research Institute to come out to Tranquilo Bay and do their research.  On March 9, we had a group of three scientists come out to take some photos and videos of the poison dart frogs interacting with robot frogs.  They put a number of colored robot morphs in play with our resident frogs to see the interaction between the real frog and the robot.  The real frog did not enjoy any other frogs moving in on his territory.  We hope you enjoy the video they shared with us as much as we have.

Variable Seedeater Song Mimicry

Today’s post is by Scott Viola.  Our children, as some of you may know, learned all 200 yard birds we have at Tranquilo Bay for their science class last year.  Scott truly took to the birds and was especially interested in their songs and sounds.  He has learned to identify many of the birds by sound as well as visually.  Here is a report he prepared for me about a strange phenomenon he encountered.

Panama Bird Song Mimicry

I have acknowledged a phenomenon on which I can find almost nothing: the Variable Seedeater mimics other birds’ songs.

For months after learning the Variable Seedeater’s song in Bocas del Toro, Panama, it made me think of rubbing a wet window with rubber. One day around New Years, I was walking in a semi-open area less than a hundred feet above sea level and heard a string of bird songs issued back-to-back from an elevated position. I was mystified, there being nothing that I could see. I considered that someone had put a playback speaker in a tree, but that was unlikely. After a few minutes, I saw a small, black bird exit the tree, and the calls ceased. I knew what it was, a seedeater or seedfinch, but I didn’t consider that it could have been the thing making the noise. A few days later, I heard it again in a nearby location. This time, I had a clear view and identified it as a Variable Seedeater.

I took two recordings of it singing, and later made videos with text on-screen notifying what bird song it was imitating. I have observed it mimicking Red-lored Parrots, Blue-headed Parrots, something that I believe is based on the Groove-billed Ani or the Common Black Hawk, Black-cheeked Woodpeckers, Blue-gray or Palm Tanagers, Tropical Gnatcatchers, Yellow-bellied Elaenias, Great Kiskadees, Boat-billed Flycatchers (probably), and Roadside Hawk, all of which are common in the area. The seedeater also has a “Brr brr Brrr” sound, and a distinctive, high-pitched “eaw.”

It doesn’t include all the birds every time it sings, but there is a loose order in which it tends to put them: parrots, the Ani or the hawk-like sound, and the rest, often with the Black-cheeked Woodpecker next to the flycatchers. The song lasts around seven to eight seconds, with 3-6 dedicated in the beginning to the parrots, the Ani-like song, and its own add-ons.

The song also changes depending on region, as can be seen on http://xeno-canto.org/explore?query=variable+seedeater. I believe this is caused by the birds it mimics, which are different everywhere. On Xeno Canto, I managed to identify a parrot in the midst of unfamiliar noises. The sounds don’t even make me think of birds; they are higher pitched and from a different place, making it sound like the song I had heard before my epiphany. The seeming randomness is stated in every Variable Seedeater resource I can find, except for one. At “The Sights and Sounds of Costa Rica” (http://www.naturesongs.com/CRsounds.html), the author wrote in the section for the Variable Seedeater that it mimics, and had two recordings that clearly contained mimicking. He was hearing the same thing I did. In them, I can tell that the seedeater mimics bird sounds. In one, I hear a Black-cheeked Woodpecker.

Introduced Species

Today, I am going to talk about a couple of birds that were introduced by humans in Panama (and other countries): House Sparrow (Passer domesticus) and the Tropical Mockingbird (Mimus gilvus).

The definition of an introduced species or non-native species (plant or an animal) is that it (said species) does not naturally belong to a specific area. We, humans, have been moving plants and animals around the globe for a very long time. There are many reasons why introduced species are moved from one place to another.   To mention a few: as a source of food, to control pests or simply because its pretty. Sometimes the introduction of this species goes well, and solves a problem, but the completely opposite can happen, and it turns into a pest that messes up the order the ecosystem.

It is very well documented how the House Sparrow was introduced in to the United States, but not on the rest of the continent. Since 1850 or 1851 the attempts to introduced the species in Brooking, New York began, and in a period of about 50 years, the species was found around the entire country.

Introduced Species Panama

Native to Eurasia, the House Sparrow was brought in to North America, apparently for a few different reasons: 1) to control a pest of canker worms that was affecting the trees of Central Park, 2) to bring birds that were familiar to the immigrants, or 3) just because they are pretty. In Panama, this species is usually found in the lowlands, near humans, often in small flocks.

Escaped and released pet birds are another way that a species makes its place in a country. Now, I am taking about the Tropical Mockingbird (Mimus gilvus), a species introduced from Colombia around 1932. It was first documented at the Canal zone after 1928 (one report in 1932 by Deingnan (Wetmore et al. 1984)). Now it’s found in both urban and suburban areas.

Birdwatching Panama

This species it is not common in Bocas del Toro. We have only seen a few individual birds in over 10 years birding the province, but just a few days ago, Scott Viola (Jay’s son), told me about a Tropical Mockingbird he saw on Isla Colon, which might be the first observation on that island for the species.

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Frog Trip

Poision Dart Frog Tranquilo Bay

Not long ago we had some guests that wanted to look for frogs. They were specifically looking to find some other variations of the very famous Poison Red Frog (Oophaga pumilio). So, we went to Popa, a nearby island in the Bocas del Toro Archipelago

At the Tranquilo Bay we have two morphs, that are quite similar, the bright orange, almost red with light blue toes and fingers and the bright red with tiny dots on the back.

Frog Photo

One of the morphs of the Poisonous Red Frog (Oophaga pumilio) found on Popa Island.

During this trip to Popa Island we got to see some nice variations in color of the Oophaga pumilio, and we also got great looks and pictures of some other species.

Poison Dart Frog Bocas del Toro

Another coloration of the Poisonous Red Frog (Oophaga pumilio) found in Popa Island.

I have to admit that I never get tired of watching the incredible variation in color of O. Pumilio. It isn’t every day that we get a photographic opportunity to capture a photo of the elusive, and very fast amphibian, the Lovely Poison Frog (Phyllobatrs lugubris).

Frog Morphs Panama

Lovely Poison Frog (Phyllobatrs lugubris)

And if the morning could not get any better, we also found another small inhabitant of the rainforest, a Talamanca Rocket Frog (Allobates talamancae), that showed up and stayed calm for us to photograph him as well.

Frog Photo Safari Panama

Talamanca Rocket Frog (Allobates talamancae)

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