The
Tangerine Darter Percina aurantiaca is a large darter that is common in the
Tennessee River drainage. It darts among the spaces between boulders
and cobbles that form the streambed.
Watch as the Tangerine Darter makes short darting movements in this underwater video (video courtesy of Ed Scott).
Tangerine darter Percina aurantiaca Photo by Brett Albanese. Source |
The
tail-slap
Thresher
sharks (Alopias spp) use their long tail to daze, smash, or kill schooling prey fish, such as
sardines. Watch this Thresher shark hunt with its tail! Click here for the video. Simon
Oliver and his co-investigators at the School
of Ocean Sciences, Bangor University, videotaped thresher sharks and discovered
that the tail-slap can be administered either sideways or overhead, depending on the alignment of
the sardine bait ball. After the
tail-slap, the thresher shark turned 180 degrees and consumed the dead and/or
stunned sardines. The sequence occurs
quickly, lasting only 1.13 to 3.40 seconds.
During the strike, the average speed of the tip of the thresher shark
tail was 14 meters per second!
Sequence of still images of thresher shark body movements throughout the tail-slap. Photos from Oliver et al. (2013). |
In
contrast to the active tail-slap hunting strategy, gars (Lepisosteidae) are
sit-and-wait predators that passively wait and then ambush prey. This video from the clear springs of Florida
show the coloration of the Florida Gar Lepisosteus
platyrhincus and its dominant behavior, the sit and wait posture. Most
of the time the gar lies motionless near the water surface. When a prey fish is nearby it will slowly
stalk until its head is positioned laterally to the prey fish. They then use a rapid sideways lunge of the
head during the strike and impale the prey on the numerous sharp teeth. . This lateral
lunge lasts only 25-40 milliseconds (Porter and Moto 2004).
Florida Gar Lepisosteus platyrhincus Source |
The
Jump
Fish
have both a sustained and burst swimming mode. One unusual behavior is the
jump, where a fish uses the burst swimming mode to leap clear from the water. Many times I have seen the jumping behavior of Common Carp Cyprinus carpio. However, I have no satisfactory answer to “why do carp jump?”
My favorite hypothesis is that the jumping behavior forces more oxygen
over the gills. But no one really knows.
But look at that carp jump!
Tambaqui
Colossoma macropomum jump for a different reason.
In the flooded forest of the Amazon the Tambaqui jumps to eat tree fruits and nuts.
The Tamaqui deposits the tree seed after passage through the gut,
thereby dispersing the seed. Watch the Tamaqui jump to capture a fruit from a tree.
The
Camouflage Carpet
Wobegong,
or carpet sharks (family Orectolobidae), are named for the ornate
pattern that resembles a carpet. Like a swimming carpet, the well-camouflaged Wobegong Carpet Shark moves along
the bottom. Watch the slow swimming camouflaged carpet shark! When
it holds a single position the wobegong becomes an ambush predator and swallows
prey whole. Watch the swallower.
The
Mimick
Ornate Ghost pipefish Solenostomus paradoxusmimicks soft
corals, hydroids, whip corals and gorgonian corals. The small protrusions that cover the animal's
body help break outline so it blends with its complex microhabitat. Watch
that pipefish! It’s not so much the movement
as the mimicry.
Ornate Ghost pipefish Solenostomus paradoxus Source |
The
Beach Burrower
California grunion, Leuresthes tenuis, and the Gulf grunion Leurestheses sardinas provide a easy-to-observe beach
burrowing behavior at high tide during their breeding. You have to watch that fish. Watch as the female grunions burrow into the sand to deposit their eggs.
Grunion life cycle is synchronized by the lunar cycle where breeding occurs at high tides. Illustration by Greg Martin |
References
Oliver SP, Turner JR,
Gann K, Silvosa M and D'Urban Jackson T 2013. Thresher sharks use tail-slaps as a hunting
strategy. PLoS ONE, 8 (7): e67380.http://dx.doi.org/10.1371/journal.pone.0067380
Porter, H.T. and P.J.
Moto 2004. A comparison of strike and prey capture kinematics of
three species of piscivorous fishes: Florida gar (Lepisosteus platyrhincus), redfin needlefish (Strongylura notata), and great barracuda (Sphyraena barracuda). Marine
Biology 145:989-1000. http://link.springer.com/article/10.1007/s00227-004-1380-0
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