February 28, 2013

Where Did The Roadside Hawk Live Before There Were Roads?

The Roadside Hawk. Image by Liz Paipay.

Walk or drive along virtually any road in the Amazon and you’ll hear that unique screech of a roadside hawk and look up to see one perched in a tree. On a particular two mile road I used to walk daily I would typically see three to four of these birds of prey acting true to their name- along the side of the road.

But wait- there haven’t always been roads in the Amazon, they were created by humans! I wondered where they are found naturally, in regions without large clearings like roads as the forest used to be. The answer? Typically either along a river, or in the forest, but in fewer numbers. 

Being a visual predator, there is a definite advantage to being in an area like a road- prey are probably easier to see than in the dense rainforest. For some reason, roadside hawks in particular have adapted to this roadside lifestyle more so than other birds of prey, and it seems to have made them more prevalent than ever.

One study compared the roadside hawk nesting activity in an area of untouched rainforest with an area with slash-and-burn farming landscape. The slash-and-burn area likely had roads in it, and at the very least represents a more open landscape for the purposes of our comparison. 

What did they find? In the open farming landscape, there were more nests, more young raised per pair, and a higher portion of breeding vs non-breeding pairs. They’re bringing home the same amount of food for their young, but the open area appears to allow more nesting and predation opportunities in general and is thus able to support a larger population.

This is an example of when a human interference and habitat disturbance can appear to ‘help’ a population. But more numbers doesn’t necessarily mean we are helping these birds. Many animals end up falling ill to disease when they are in an unnatural higher density due to human activity (like high density coyotes in neighborhoods suffering from mange in the United States), and the prey that the birds are feeding on may suffer from an unnaturally high mortality rate. 

While it doesn’t appear to be affecting the birds negatively at this point, it is a strong lesson that as we modify the rainforest, we modify the animals within, as well.

February 23, 2013

What wildlife can you see along the Tambopata?

The Andes Mountains can be seen from the Tambopata

Riding in canoes is an experience that is not just for the sake of transportation. It also provides an incredible opportunity to see and photograph wildlife. 

Here's a list of some of the more notable animals we've seen in the last few months:
-Giant Anteater
-Red Howler Monkey
-Harpy Eagle
-Black-and-White Hawk Eagle
-Red Brocket Deer

Why can we see so much wildlife while on a boat? A few reasons. Many animals, like jaguars, rest by the river, providing an excellent opportunity to photograph them. Also, virtually all mammals in the rainforest can swim and tend to cross the river on occasion, so you can even find a sloth slowly making its way across!

What's that log in the water?

It's a giant anteater swimming! 
Image by John Hannaford.

Also, many animals aren't sure how to interpret seeing a boat- while a jaguar may hide from you when you're on foot, they typically don't interpret you as a threat when you're in a boat. This works great for us, because it allows plenty of time to get the perfect photo!

    Jaguar seen along the river from a boat. 
Image by Liz Paipay.

February 18, 2013

Macaw Chick Update


Remember this adorable macaw from last month?

We checked in with the researchers at the Tambopata Research Center to see how he's doing. An update from Jordan Harrison, one of the volunteer macaw researchers, and it looks great:

"The Hormiguero chick is doing quite well. Healthy as he can be. His body condition score was almost perfect when we checked on the 16th for his 60 day check up. He weighs about 850 grams, feathers are developing nicely. Not even any parasites. He is a super chill chick. We took our usual measurements and he sat calmly in my lap the entire time."

Here he is, almost all grown up at this point:

Photo by Jordan Harrison

Photo by Jordan Harrison

February 11, 2013

Welcome to Tapir Eden


A group of scientists recently came together with park rangers and native communities to solve a difficult question: 

How many tapirs are there in the Greater Madidi-Tambopata Landscape of northwest Bolivia and southeastern Tambopata Peru? 

Tapir crossing the Tambopata River. Image by Jeff Cremer.

Tapirs are the largest mammal in the Amazon, but their large size doesn’t mean they’re easy to find. In fact, they are notoriously really difficult to see, and most researchers and guides I know who work in the Amazon have only seen a handful due. These odd-looking creatures look similar to a horse but are actually more closely related to the rhinoceros. 

My only sighting wasn’t by my eyes, but by my camera trap I set up, a video of which can be seen here. Researchers for this study used this same camera-trap technique, in which you put motion and infra-red detecting cameras in areas of high mammal activity in order to monitor and detect populations. 

While many mammal studies rely entirely on camera trap images, these researchers also included the one thing that could give them insight to how the tapir populations have changed over time: humans. 

They interviewed park rangers and native hunters to further gain insight into tapir behavior, tapir hang outs, and tapir numbers. The combined data suggested that tapir populations are increasing throughout most of this range due to ecotourism projects and government efforts which help protect the forest and minimize hunting.

The analysis suggested that there are between 15,000 and 35,000 tapirs in this range- possibly more tapirs than there are humans! To read the full study, check it out here.

Note the ticks on the tapir's head and the odd snout.
Image by Jeff Cremer.

February 04, 2013

Stephanidae- An encounter with a rare parasitoid wasp


This odd-looking creature is commonly known as the ‘crown wasp’ due to a ring of tubercles on its head but is known by scientists as a stephanid. 

Stephanus is greek for crown, thus, Stephanidae.

Its strange body structure can be hard to make sense of, so let me try and explain: The orange/brown part to the left is the head, to the right of that the thorax with the wings attached, and the part sticking up into the air is the abdomen, making up the three major segments of an insect.

But what is that long needle-like structure on the right?

That is the ovipositor, the technical term for an insect’s egg-laying device.
The wasp uses this ovipositor to stab beetle larvae and lay eggs in them, which it does by using its legs to sense vibrations from beetle larvae living inside the rotten wood it has landed upon. After a few days, the deposited egg hatches and a wasp larva develops inside the beetle larva, eventually killing it and emerging as an adult, which then flies off to stab a beetle larva elsewhere in the rainforest and start the process all over again...

Some parasitoid wasps actually use a form of echolocation (just like a bat would) to locate their prey. They have modified antennae that tap the rotten wood and specialized ears on their legs that can hear the tap’s echo off of a larva and locate it that way.

This particular rotting tree had several of these wasps on it, so clearly there were some stab-worthy beetle larvae within.

Note: this wasp is a parasitoid because it kills the beetle larva host, opposed to a parasite which just feeds on it but lets it live.

Read more about these wasps here.

February 01, 2013

When It’s Macaw Breeding Season, Researchers Get To Action

A seven-week-old scarlet macaw nestling getting weighed. Doesn't it look like it's smiling?
Image by Phil Torres

Researchers take measurements on a 1-week-old macaw chick.
Image by Phil Torres

The Tambopata Research Center has hosted world-renowned macaw research for 20 years now, with researchers analyzing macaw activity, monitoring the fruiting trees they feed on, and overall keeping an eye on the macaw population.

But this time of year is a special time of year for the researchers. As rainy season comes into effect, the macaws start laying eggs and the researchers begin closely monitoring the nests and measuring the chicks as they develop.

jordan harrison
Researcher Jordan Harrison climbs
up to a macaw nest. Image by Phil Torres.

If their research wasn’t cool enough already, they use technical tree climbing techniques to go up 30m-40m into the trees to gain access to the nests. Pretty awesome science if you ask me.

Into the Field

I had the pleasure of joining them and observing one of their morning climbs and chick measurements. In fact, any visitor to the lodges, including tourists, can tag along with the researchers in this activity.

It involves a team of at least three researchers, one doing the climbing, chick removing, and nest check while the others take the chick (which has been lowered in a bucket) and record size, weight, and other observational data.

The chick I was lucky enough to see was a one-week-old red and green macaw. One of the strangest looking creatures I’ve ever seen, it’s hard to imagine it will turn into one of the most beautiful birds in the rainforest.

The chick was plump and healthy by all accounts, and after the measurements were done the chick was raised back up, put back in its nest to await its parents return with a crop-full of food.

peru amazon rainforest
A one-week old red-and-green macaw chick getting weighed by researchers.
Image by Phil Torres
Why Do the Research?
Macaw populations are at risk for a variety of reasons. Habitat destruction and the illegal pet trade have taken a tole on wild populations. Some species also require a specific type of tree to nest in, and at times those trees come under high demand from loggers.

By studying these populations, their breeding, and their genetics, researchers can arm themselves with the knowledge necessary to keep populations from going extinct. The information gathered here in non-threatenedTambopata- for example, successful artificial nest designs-  can be used in areas where macaws are endangered, like Costa Rica and Mexico.

Led by Dr. Donald Brightsmith, this project has published many breakthrough studies, including figuring out why macaws eat clay (for the salt!), what influences nestling survival (macaw fights!), and why they lay four eggs but only raise one or two young.

Red and green macaws gather on a claylick along the Tambopata. Hard to believe the above chick will turn into something so stunning. Image by Jeff Cremer.
To volunteer as a researcher for this project, visit http://macawproject.org/
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