Costa Rica - August 2014 - Caño Negro

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Costa Rica - August 2014 - Caño Negro

Post by chrish »

This is a continuation of my trip to Costa Rica from August.
I know some of us get tired of trying to get through a 200 photo mega post, so I will break this trip up into
Aguas Zarcas Area - Frogs
Aguas Zarcas Area - Reptiles
Caño Negro Area - You Are Here
Sarapiqui Area - coming soon

While we were staying in the Alajuela region, we decided to make a couple of day trips up to an area of swampy marsh in northern CR up on the Nicaraguan border. I have a particular love of tropical grasslands and marshes. I think they are underappreciated by herpers. Most herpers tend to go to tropical areas and head straight into the rainforests and stay there their whole trip. I think this is short-sighted. Sure there are neat critters in the rain/cloud forests! But the marshes and grasslands of the tropics also have high diversity and generally you see a lot more critters than you do in the rainforest. Herping in rainforests is tough sledding. You see a handful of specimens or species a day. Get into a tropical grassland or marsh and your species count goes way up. Of course, being a birder also influences this choice since there are interesting tropical grassland birds. This area has almost endemic birds like the Green Ibis and Nicaraguan Grackle that are hard to see anywhere else.

One difference about being up in a tropical grassland vs tropical rainforest is that people are always surprised when they walk in a rainforest how few mosquitoes and other biting insects there are. That's because the mosquitoes all live in the tropical grasslands instead :shock: !

!! CAUTION - BIRD CONTENT !! - if you are completely herp-centric and don't really appreciate the living world, you might need to scroll down a few centimeters!

To be honest, the main reason I wanted to go up there was to have another shot at my nemesis bird. I have looked for this species in 5 different countries in good habitats at the right time of the year and failed repeatedly. As we drove up into this marshland, I was scanning ahead of the car as we looked at birds right next to us and to my amazement, after 20 years of searching, I finally spotted this - a frickin' Jabiru!!


Fortunately, it allowed me to get quite a bit closer -


(If you are interesting in seeing the other trip birds, you could look at my post in the birding forum)

Fortunately for you, dear reader, there were actually herps in this area as well. :lol:

This area contains a wildlife refuge that consists of a series of marshy lakes. If you drive into the town of Caño Negro, you can hire a boat to take you around the edges of the lakes to look at wildlife. Highly recommended trip, particularly if you like birds. When we got there, however, it was non-tourist season and we had to ask around a bit to find someone to take us out. Fortunately we did and our guide piled us in his boat and took us on a two hour cruise around the lakes. It was amazing.

It was on this boat tour that we got our first looks at Caiman (Caiman crocodylus). They were used to the boats and let us get pretty close. Unfortunately, it was dark and overcast and lighting wasn't good (thus the ISO 6400 shot) -


There were also a large number of Central American Tree Appendages (Iguana iguana) on the trees overhanging the lake edge -


Of course, we stayed after dark in the marshy area to see some other herps. Being the beginning of the rainy season, we weren't disappointed.
We found a few snakes DOR up there, but didn't see any live ones.

I would love to have seen this Costa Rican Coralsnake (dumb name!) (Micrurus mosquitensis) alive -


and this was the only Cloudy Snake-eating Snake (Sibon nebulatus) we saw all trip -


But the real bonanza up here for me was the frogs of these marshy grasslands.

There were a variety of species some of which we had seen further south, but also some new ones that only reach northern Costa Rica.

Choruses of Vaillant's Frogs (Lithobates vaillanti) were calling in the deeper open water areas of the marshes.


Their calls are strange and complex. I thought it was just water bubbling under a road culvert when I first heard it from a distance -
(The metallic puk, puk in the background is the Sabinal Frog (Leptodactylus melanonotus)) -

One of my favorite little frogs of the central American grasslands is the Yellow Treefrog (Dendropsophus microcephalus)

I didn't photograph any in CR, but here's a photo of one from Chiapas, Mexico -


and their funny raspy little calls from here in the Caño Negro area -

The other common little yellow frog in this area is the Olive Snouted-Treefrog (Scinax ochropheus). I felt bad for these little guys because every time I put a flashlight on them for more than a second or two, the mosquitoes would find them and brutalize them.


Here's one individual (the one feeding all the mosquitoes above) -

and a chorus of Scinax -

These little froggies had to be careful in these shallow grassy marshes along the road. There were other eyes looking from small frogs as well in the grasses. We spotted at least a dozen of these little frog-munchers -


Up at this northern end of Costa Rica you get the southern end of the range of northern CA species,

like the "Mexican" Treefrog (Smilisca baudinii) again feeding mosquitoes -


and its piercing call -

Toadwise, you get the poorly-named Southern Gulf Coast Toad (the real Incilius valliceps), which looks and sounds like its northern cousin from the my backyard -
(Again note the friendly mosquitoes. Getting the clue about mosquitoes here?)


and their call is almost identical to nebulifer as well -

So, even though we didn't see the diversity of reptiles we did in other places, mostly that was because we only spent a few hours here and most of that was in a boat, or at night. In those few hours we saw a lot more individual herps than anywhere else in CR.
If you are traveling to Costa Rica and want some habitat diversity, give Caño Negro a visit.

Next stop - the lowlands around Sarapiqui.


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Re: Costa Rica - August 2014 - Caño Negro

Post by Roki »

Cool posts. I never get enough of Costa Rica. The place is just amazing. Looking froward to your Sarapiqui section. Also great job on finding the Jabiru that has been a quest for you it sounds like. I know the feeling. I have a few species like that where you have done all the homework, planned everything right, and then nothing. Such a great feeling to finally find that one that keeps getting away.

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Re: Costa Rica - August 2014 - Caño Negro

Post by Phil »

Again, fantastic post! I'm feeling pretty bad for those frogs, though; I don't remember the mosquitoes being too bad when I went down there!

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Cole Grover
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Re: Costa Rica - August 2014 - Caño Negro

Post by Cole Grover »

Love the Jabiru and the frog call recording give a sense of place. Nice post(s).


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