The oyster toadfish, also known as the ugly toad, oyster cracker, oyster catcher, and the bar dog (Opsanus tau) is a species of fish found in the Atlantic Ocean, along the North American coast from the Caribbean to the US-Canadian boarder. As juveniles they reside in coastal estuaries, and as adults they move out to shallow oyster reefs and rocky intertidal areas. Bar dogs are noted for being particularly tolerant of polluted waters.
The oyster cracker begins its spawning period in May and continues through August. Males and females move into the estuary, where the males excavate nests under rocks and make calls known as 'boatwhistles' using their swim bladders. Attracted females deposit a clutch of eggs for the male to fertilize, then leaves. The males remain and protect the nest; the eggs hatch after about a month, and juveniles remain with their fathers for another week or two. Young ugly toads reach full maturity at anywhere from 2–7 years and have a lifespan of 8 years.
Adult O. tau can reach anywhere from 30-43 cm (12-17 in). they have oblong, flat bodies which allows them to fit under rocks and into tight crevices. They tend to be drab in color, usually olive or brown with black mottling, although they do have some ability to change their color to match their surroundings. The ugly toad is named for its distinctive bulging eyes and wide mouth, which is lined with fringes that act like whiskers to help them detect prey.
Oyster catchers feed mainly on oysters, as well as crabs, squid, and marine worms, which they ambush at night and crush with their powerful jaws and strong teeth. Few other fish go after adult O. tau due to the fish's sharp gills and venomous spines. However, they are known to be predated upon by dolphins, sharks and marine birds like cormorants.
Conservation status: The oyster toadfish is classified as Least Concern by the IUCN. They have a large, robust population that's resistant to pollution; however, they may become vulnerable to overfishing or the loss of their primary prey.
Searching for toadfish on Tumblr seems to mostly bring up the Splendid Toadfish (Sanopus splendidus) (as well as unrelated fish that are also called “toadfish” or “frogfish” such as some puffers and anglers)
And while the Splendid Toadfish is indeed quite splendid, I was really hoping I could find any posts featuring its cousin the Whitespotted Toadfish (Sanopus astrifer). Alas, I could not, so I must once again take matters into my own hands.
A species of toadfish found in the Caribbean Sea and Atlantic Ocean along the coasts of Central and South America from Honduras to Brazil. It is the largest toadfish, reaching a length up to 57 cm (22 in) and a maximum recorded weight of 2.3 kg (5.1 lb). This fish is found in local commercial fisheries and the aquarium trade.
Tetraodontiformes. This order contains many fishses with unusual body structures, such as boxfishes, which are boxy as the implies, pufferfishes, which are round and able to inflate, and the ocean sunfish, the largest bony fish.
Batrachoidiformes. This family is made up of toadfish, ambush predators that hide on sandy and muddy substrates. They also ''sing'' using their swim bladder to attract mates.
Anatomy: toad-like appearance; usually scaleless; large head; eyes set high on head; large mouth; often decorated with barbels and skin flaps for camouflage; sharp spines in first dorsal fin, which are venomous in some species
Diet: molluscs, crustaceans, worms, smaller fish
Habitat: oceans worldwide; some are found in brackish water and one subfamily is found exclusively in freshwater habitats in South America; they are bottom-dwellers, ranging from near-shore areas to deep waters
Evolved in: Late Cretaceous
(source)
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Propaganda under the cut:
Male toadfishes are some of the best fathers in Actinopterygii. Males make nests and, like their amphibious namesakes, attract females by "singing". This is achieved by contracting muscles on their swim bladders to release air, making hums, whistles, grunts, croaks, and “boatwhistle” sounds that can be loud enough to be clearly audible from the surface. (Listen to them here) Each male attracts numerous females to his nest, so his eggs come from multiple mothers. The male guards the nest against predators and cleans the eggs, and he will not leave his nest to hunt, so he must survive on a limited supply of food. Once hatched, the larvae will cluster around and hide behind the male until they are large enough to fend for themselves.
Toadfish can survive out of water for as long as 24 hours, and some can move across exposed mudflats at low tide using their fins
The Oyster Toadfish (Opsanus tau) (image 2) has a variety of common names, including Oyster Toad, Ugly Toad, Oyster Cracker, Oyster Catcher, and Bar Dog. In 1998, NASA sent an Oyster Toadfish (which can survive in poor conditions with little food) into space to investigate the effects of microgravity on the development of otolithic organs. The study found little difference between terrestrial development and those in space.
The endangered Splendid Toadfish (Sanopus splendidus) (image 4) is unique amongst toadfish for its vibrant colors.
The Grunting Toadfish (Allenbatrachus grunniens) (image 1) is sometimes kept in freshwater aquariums and it can survive in them, however, it is a brackish fish and a salty environment is more ideal.
The Three-spined Frogfish (Batrachomoeus trispinosus) is said to be the only fish known to “cry like a baby” and produces complex, non-linear calls. Other fish can only make simple linear sounds, while human babies (and other mammals) use non-linear sounds in their calls, which other animals tend to associate with a sense of emotional urgency.
The endangered Two-faced Toadfish (Bifax lacinia) is known only from the coast of Oman. Its population continues to decline due to threats from habitat destruction, oil spills, pollution from runoff, bycatch, and more.
Midshipman Fish (genus Porichthys) are unique for their rows of button-like, bioluminescent spots (image 3), which supposedly resemble the buttons on the uniforms of young naval officers.
Midshipman Fish have three sexes: the largest are the females, the second largest are the Type I males which also have large vocal organs, while the small Type II males make up for their stature by having reproductive organs which are seven times larger in size than those of Type I males. Type I males will attract females to their nests with their beautiful voices, coax them to lay eggs, and guard them. In contrast, the Type II males do not build nests or attract females on their own. Instead, they are “sneaker males”. They let Type 1 males do the work of attracting females, sneak up to their nests, and deposit their own sperm on the eggs there.
Midshipman Fish can decrease their own hearing sensitivity by stiffening their inner ear hair cells while they are vibrating their calling muscles. This behavior is also found in bats, and is being researched to see if we can find a similar mechanism for humans to turn down their ear sensitivity in order to retain their hearing longer.
The Plainfin Midshipman (Porichthys notatus) is known for waking up houseboat residents along the California coast, and is the namesake of The Sausalito Humming Toadfish Festival. The yearly festival had a marching kazoo band, “toadfish-flavored” ice cream, and a marine biologist as Grand Marshal. The festival ended in 1990 due to the Plainfin Midshipman slowly disappearing from Sausalito, but there are hopes the festival may return.
On August 9, 1974, composer Charlie Morrow performed a “concert for fish”, on a boat in the middle of Little Neck Bay in Queens, NY, using what he understood to be decoded toadfish language. New York Times music critic, John Rockwell, wrote a review of the unique art piece, but unfortunately I don’t think the concert was ever recorded.
