Saturday, July 13, 2013

Blenny fight! A dominant male protects his food (little neck clam)

A dominant male (blue spot on the dorsal) fights others away from the freshly shucked clam in our piling exhibit

Feather blennies are named for the two cirri or "feathers" over their eyes

Blennies, feather blennies in particular, are feisty little fishes (as seen in the video). Blennies are a group of small saltwater fishes that remain around relatively shallow water structure, such as oyster reefs and pilings throughout their entire lives. Once they have established a territory, they vigorously defend it and often battle each other in close quarters for food and mates. Productive habitats may house a blenny or mated pair of blennies every couple of square feet, each patrolling their respective property with head up and fins extended ready to scrap. One reason they defend their territory so aggressively is that prime real estate is hard to come by and even harder to get to. These pugnacious little fishes are not strong swimmers, rather they rest upright on their broad pectoral fins and use their broad rearward fins to propel them quickly forward in lightning fast bursts - usually at a trespasser on his territory - and not for long distances.

Striped blennies often lay on their sides inside seashells

There are a few other species of blennies occasionally found in Virginia, but the most common by far are the feather blenny Hypsoblennius hentz, and the striped blenny Chasmodes bosquianus. Though these two are related, the striped blenny is a much less aggressive species and therefore easier to house in an exhibit with other species. They often are found in proximity to each other and a host of other species as well.

Naked gobies can often be found with blennies among oyster shells


Oyster reefs and grass beds are important habitat for a huge variety of similar fish species such as the naked goby, skilletfish (above - pictured stuck on the acrylic with a "suction cup" on its belly) and the much maligned oyster toadfish (a pile of them pictured below)

 Innumerable crabs and shrimps also hide in the nooks and crannies of the oyster shells. 
      
 Grass shrimp, sometimes called ghost shrimp are an important prey species

All these animals occur in such densities because there is an enormous amount of prey and forage items available in these areas, mainly invertebrates and algae. These structure communities in turn attract a multitude of predatory fishes attracted to a high concentration of prey. Fisherman may not be aware of exactly why oyster reefs draw sea trout, red drum, croaker and stripers, but they certainly know that they do. We attempt to represent these structure-based communities in our "Piling" exhibit that showcases blennies, gobies, skilletfish, sheepshead, scup and a variety of crab species.But as noted earlier the feather blennies rule the tank, nipping at fins and challenging much larger fishes, making it difficult to display more than a dozen or so fishes at a time.





1 comment:

  1. Great post. I can't believe that I just found it!

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