Sargassum Community

This article was written in June 2015, and published in July 2015.

 

Today I wanted to share a collecting trip of a different sort: sargassum sampling.

 

Sargassum
Sargassum

 

Sargassum is a genus of brown algae, most widely recognized for its holopelagic (always free-floating) forms, S. natans and S. fluitans. These algae form large mats in offshore waters, blown together by winds and currents.

Hard onshore winds in recent days have blown in a lot of the free floating Sargassum from offshore, and I took this opportunity to do some dip net sampling. I chose the docks at the Morehead City waterfront, as proximity to Beaufort Inlet, and large docks, made for easy access to the sargassum floating by.
 

 
Sargassum provides a plethora of juvenile fishes with shelter, and a source of food in offshore waters. Most fishes do not eat the sargassum, but rather prey on other animals that are attracted to it. It is worth noting that a majority of the offshore fishes will not stick with the sargassum as it drifts into inshore waters, and many inshore fishes will associate with the sargassum once it blows inshore. In other words, some of these species below may not normally be associated with sargassum communities. With that said, I definitely caught a mixed bag of fishes and inverts!

Red colored species names are normally not associated with sargassum, and likely attached once it had drifted inshore.

 

Lesser Blue Crab - Callinectes similis
Lesser Blue Crab – Callinectes similis

 

Greater Amberjack - Seriola dumerili
Greater Amberjack – Seriola dumerili – Juvenile

 

Gag Grouper - Mycteroperca microlepis
Gag Grouper – Mycteroperca microlepis – Juvenile

 

Bermuda Chub - Kyphosus sectatrix
Bermuda Chub – Kyphosus sectatrix

 

Lined Seahorse - Hippocampus erectus
Lined Seahorse – Hippocampus erectus

 

Almaco Jack - Seriola rivoliana
Almaco Jack – Seriola rivoliana – Juvenile

 

Sargassum Nudibranch - Scyllaea pelagica
Sargassum Nudibranch – Scyllaea pelagica

 

Tripletail - Lobotes surinamensis
Tripletail – Lobotes surinamensis – Juvenile

 

Planehead filefish - Stephanolepis hispidus
Planehead filefish – Stephanolepis hispidus – Juvenile

 

Permit - Trachinotus falcatus
Permit – Trachinotus falcatus – Juvenile

 

Common Dolphin - Coryphaena hippurus
Common Dolphin – Coryphaena hippurus – Juvenile

 

Brown Grass Shrimp - Leander tenuicornis
Brown Grass Shrimp – Leander tenuicornis

 

 

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