Our Day as Field Scientists

In a mangrove in Koh Lanta, we got to experience even for a short period of time what it’s like to study fiddler crabs. We were split up into two groups under the supervision of Mullica Jaroensutasinee, Walailak University’s Fiddle Crab expert, to study feeding and fighting habits. I was a part of the group that studied fighting among male fiddler crabs. The crabs would initially pick a fight with another crab beginning a sort of dance of intimidation. The more intimidating crab would run towards the other one until it would back down or retreat sometimes without even actually physically touching the other crab. Other times they would fight with claw to claw combat interlocking their claws and jab at each other.

The other group studied to see if feeding rates were different between males and females, counting each time the crabs claw was lifted to it’s mouth to see how many times the claw scooped food per minute. This is significant because males, due to sexual selection, have one larger claw that serves no significant role in survival, where as females have to nimble claws.

To further study the crabs interactions we filmed the crab fights and feeding habits, where we could study them and draw further conclusions on their behavior before presenting our findings to our classmates and Mullica.

Our time in the field was one of my favorite experiences of the trip with hands on learning as we got very involved in the study and invested in watching the crabs. Here are some of the crabs we saw as well as some other key species in Mangroves: