Mexican Mammal Study in Coffee Farms

March 12, 2014 by Amanda Caudill


We completed our second to last sampling session yesterday and then went to a huge waterfall after we cleaned up the sites for this sampling session. It was so beautiful! We would have never found it if it weren't for the guide who works with us at one of the farms.

Field crew in front of waterfall

We treated ourselves to a lunch of beans, rice, tomatoes, and guacamole—a nice change from our constant field lunch of peanut and jelly. I tried to explain to the guide (to whom we bring a PB&J sandwich every day) that normally people from the US do not eat this much peanut butter. I'm going to need a peanut butter hiatus when I get back home.

Nasua narica (white-nosed coati) from camera trap

Our camera traps again were really successful. We were able to detect deer, possums, coatis, agoutis, armadillo, and fox. For the small mammal traps, we saw our usual suspects—Reithrodontomys (harvest mice), Peromyscus (deer mice), and even a couple more Marmosas (mouse opossums) in the sun coffee.

The behavior of the mouse opossums is completely different from the mice which makes sense because although they are the same size as the mice that we catch, they are not rodents at all. As the name suggests, they are small opossums. They are much more alert in the bag that we use to weigh them and they occasionally do threat displays. I read that they sometimes do the "possum salute" which is holding up a clinched fist as a threat display—which I unfortunately have not seen.

Although it doesn't happen that often, it is not unusual to have unintended captures in the traps. In my previous work in Costa Rica, we caught toads, small birds, and large snails. In India, we caught a couple of chickens who would peck at the bait in the back of the trap and the door would close on their head.

For this study, our unintended captures have been lizards. It is a little startling to peek in the closed trap expecting to see a mouse and instead a lizard is staring back at you. They are sometimes tough to get out of the traps; then once they are out, make a frantic dash, sometimes running straight at you.

As for other non-mammals, there are two white geese that strut around one of the farms from this last sampling session. They are not afraid of anything. We saw them attack a lady who tried to hit them with her purse; one of them even grabbed her purse with its beak! Everyone escaped unharmed. Yesterday, we were driving behind them as they waddled down the middle of the road and the geese would not move. They actually started pecking and attacking the car!

Afternoon rains

It has been in the mid-90s here recently (not to rub it in to all of you who have been hit with a cold, snowy winter this year)—so we appreciate the cool air that the afternoon rains bring. We have had heavy afternoon rains consistently this week. I've been told that these rains have come about a month early this year.

The field crew profile this week is of Stephen Brennen, our lone Irishman on the crew. He has a master's degree in Conservation Biology and had done field work all over the world.

Why were you interested in doing this field work?

I enjoy the opportunity to work in different countries and experience different habitats and species to broaden my knowledge of ecology. In this case, the chance to improve my Spanish and see more remote regions of Mexico was also attractive.

Favorite thing so far:

Seeing the differences between each coffee farm and how they are managed either organically or not. I also enjoy handling small animals which would not normally be seen by most people.

Special skills:

Exotic tree identification and finishing left over food.