Invertebrates (animals without a backbone), like squid and jellyfish, can be hard to study because of their soft bodies — it’s not easy to attach a tag that tracks the animal and collects data. They play a critical role in the marine food web, but little is known about their natural behaviors and the influence the environment can have on them.
“Squid and other soft-bodied invertebrates have almost open circulatory systems, so they’re closely linked to their physical environment,” Aran Mooney, a biologist at the Woods Hole Oceanographic Institution (WHOI), explained in a news release. “As the ocean environment changes, they probably change a lot in response.”
In order to determine how a changing environment is impacting these creatures, Mooney and his collaborators created a brand new kind of data-logging tag: ITAG. It’s designed specifically for small, delicate invertebrates.
One of the biggest challenges the team faced when designing the tag was to minimize the size while maximizing the amount of data it could collect. The ITAG measures about 4.25 in x 2.5 in x 1 in (108 mm by 64 mm by 28 mm) and is capable of collecting data on ocean conditions while measuring the individual’s response to their physical environment.
“We wanted a tag that would be able to tell us what the animal is doing at that depth—is it hovering or swimming faster or slower? When squid go down to a couple hundred meters, are they foraging at night at that depth, or are they resting and getting away from top predators? What are their respiration rates? These are the types of behavior questions we wanted to answer,” Mooney said.
Check out this short video clip to see what it looks like when it’s attached!
To learn more:
- Read the WHOI news release: Novel Tag Developed for Squid, Jellyfish
- Read the full paper: ITAG: an eco-sensor for fine-scale behavioral measurements of soft-bodied marine invertebrates
Copyright © 2015 by Marine Science Today, a publication of Marine Science Today LLC.