Spotlight on Sponges – Part III

The third and final entry in Research Scientist Dr. Alan Duckworth’s blog on sponge studies in Jamaica.

Days 9-12

 The settlement plate experiment is now finished, with plates anchored to the reef at two depths in an impact and two control locations. Now we wait 6 months to see what marine organisms have settled and are growing on the plates. To get meaningful data that encompasses any seasonal and annual effects, this experiment will run for 2 years. Ideally, the experiment should last for another year or more, but research funding always dictates what marine science you can do. 

Brown tube sponge, agelas tubulata

The next experiment is a growth study, where we tag several sponges of various species at the three locations to determine what effect, if any, coastal development has on sponge growth rates. All up, 180 sponges will be monitored over time, which means a lot of swimming to find suitable sponges to tag. The tag is nailed onto dead coral next to the sponge, so it does not interfere with its growth. Each sponge is then measured and photographed. Diving days for the growth study are similar to the settlement plate experiment, but no heavy drilling gear is needed.  

Measuring sponges

This field trip is rapidly coming to a close, with only one full day left. Before I came down I had heard of the great diving in Jamaica, and it’s true. The water is clear, warm and inviting. The local reefs are a sponge mecca, encompassing all different shapes, sizes and colors. The lack of medium and large coral reef fish is a concern, but it is not likely to change anytime soon.

Ballonfish

Eel being defensive

 Much of the success of this field trip is due to the friendly and helpful staff of the Discovery Bay Marine Lab, who I thank greatly. Lastly, I leave you with a series of photos, showing some of the visual highlights from Jamaica.

 Cheers, Alan 

Flamingo tongue on Gorgonian

Sponges

 

The giant barrel sponge - xestospongia muta

Moonrise over Discovery Bay