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Bubbles
from the Naturalist Jerry's tank - by Jerry Ligon Conspicuous coloration and animals that are toxic
go hand in hand because the animal that is toxic does not want to
take the risk of injury from a predator, therefore, the predator
recognizes the toxic potential before making the mistake. But, this
is a learned reaction between the predator and the toxic prey and
is the result of an educational session or two. The usage of such
warning coloration is known as aposematic coloration.
Pseudobiceros sp. (taken by Jim Belay, Bonaire) Above is a photo of a flatworm with conspicuous coloration that is used as a warning to fish that are predators. The effect of the toxin on the predator must be distasteful enough to deter the predators efforts to eat the prey, but not so severe to cause death, because the lesson has been lost if the predator is no longer an educated part of the prey's world. In biological terms, this type of deterrence is known as Mullerian mimicry. However, very sneaky animals have evolved to resemble the toxic animal that has been doing a lot of work to warn the predators not to feed on them and to recognize their toxic qualities by the conspicuous coloration and is called Batesian mimicry. (Terrestrially, the Monarch Butterfly is the unpalatable one (Mullerian mimicry) and the Viceroy is the mimic (Batesian mimicry). FROGFISH I have been wondering if our charismatic Longlure Frogfish is doubly protected against predatory fish. First, they are camouflaged to look identical to the sponges that they are often seen sitting on. Even the spots on their body and tail look like the excurrent canals of the sponges, which makes us divers so frustrated in trying to find them. We are amazed when we do find one that is camouflaged perfectly. The frogfish's habit of sitting motionless and by using its lure to attract its prey (usually small masked/glass gobies) makes it one of the most perfect predators on our planet. They will catch about 93% of the prey that are lured in. The frogfish has a feeding reflex of .08 seconds. (8 milliseconds) which does not give the small gobies much of a chance to escape. Secondly, if the frogfish is on bare sand or on a coral head, it obviously is not camouflaged, yet, because sponges are so distasteful to fish, it still looks like a small section of sponge that is just beginning to grow. so, the frogfish still receives protection because it looks like a piece of distasteful sponge. We do not know if the frogfish itself is distasteful. I must admit that I have an obsession with Longlure Frogfish and have been studying them ever since I saw my first one upon arriving on Bonaire in 1994. Another thing in the divers favor is the habit of a particular frogfish to remain within a few feet of where he was first seen and remain in that zone for often as long as 1 year. The black color frogfish is really deceitful, looking identical to black sponge found common on the reef. The only way that I have been able to tell that I am looking at a frogfish is that a sponge receives a dusting of sand and silt, but not the frogfish. He is usually very clean of silt and sand and looks fresh out of the box.
BOX JELLYFISH Now, a topic of current interest.
We are still waiting on the DNA results of a box jelly, found in
Brazil, that resembles the one found in Bonaire and ours might be
a new species, pending the DNA results. It has been seen on Bonaire
for around 10 years, and has the common name of Banded Box Jellyfish.
When I was doing night dives as an instructor on Bari Reef, in 1994,
I was aware of many divers complaining of severe stinging and in
severe pain, after completing a night dive on Bari. We took no chances
and would take them to the emergency room at the hospital to be
treated and usually they would be held overnight for observation
of progressively more dire consequences. These box jellyfish were
plain with no bands on their four tentacles, totally uncolored,
and on one particular night I found them in the 100's and swarming
around our pier whose lights attracted them.
Video of the Banded Box Jelly Fish(video by Marijke, Bonaire) I am wondering in this discussion about mimicry, if this"New" Banded Box Jellyfish is the "improved" type that has given it more clout against its enemies, and obviously will have more to be remembered by whenever a predator first makes contact with this toxic species. Hello to Marco, a divemaster, instructor that we really got go know and appreciate here at Sand Dollar Dive and Adventure, there is no better way to say that he is remembered than to pass on the news that HIS Seahorse at Carl's Hill, found by him on April 24, 2008 was found again on a dive that I led. It is the longest that I have had one particular seahorse under observation, and, I keep a detailed notebook filled with such dates and sightings. For example, I can tell you that the pair of seahorses at Carl's Hill and the pair at Mi Dushi, on Friday, 15 August, 2008, both pairs were within a few feet of each other, indicating courtship, and Full Moon was on the following day! So, Hello, Marco, hope you are doing as well in Holland as your old friend is at Carl's Hill. It is going on 17 months under observation. New evidence that DEET is neurotoxic should be read by all that come to Bonaire and are using DEET. Newly discovered website for information about the Marine world from National Association for the Advancement of Science (NAAS) prestigious scientific organization and open source with no need to login. It is called EurekAlert.
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