Gulf toadfish

Gulf toadfish
Gulf toadfish after being caught by hook and line
Conservation status
Least Concern  (IUCN 3.1) [1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Batrachoidiformes
Family:	Batrachoididae
Genus:	Opsanus
Species:	O. beta
Binomial name
Opsanus beta (Goode & Bean, 1880)
Synonyms
Batrachus tau betaGoode & Bean, 1880 Opsanus vandeuseniFowler, 1939

The Gulf toadfish (Opsanus beta) is a species of toadfish found in the Gulf of Mexico. ^[2]

Description

The Gulf toadfish are elongate, tapering, robust toadfish with a depressed head. They are mottled tan, white, and brown with a darker posterior end. Their caudal and pectoral fins have dark brown bars on a pale background. The bars on the pectoral fins are irregularly joined. The dorsal and anal fins have oblique alternating brown and white bars. The dorsal fins have 24 or 25 rays, and the pectoral fins have 18 or 19 rays. ^[3] Gulf toadfish commonly weigh 2 to 3 pounds (0.91 to 1.36 kg) and measure 11–14 inches (28–36 cm). However, smaller ones are sometimes caught weighing 0.25 pounds (110 g) measuring 4–5 inches (10–13 cm).

Distribution

The Gulf toadfish is found in the Gulf of Mexico commonly inshore around bridges and structure such as pilings.

Habitat

The Gulf toadfish is often found in near shore shallow sea grass beds and rocky areas. Smaller individuals sometimes inhabit discarded objects, such as jars or cans. ^[3] They prefer shallow areas near baitfish populations.

Biology

Diet

The Gulf toadfish is an opportunistic feeder and feeds on the bottom. They prefer to be near areas supporting baitfish so that they can feed without having to travel far. They also eat marine invertebrates. ^[3]

Calls

Like others of the family, gulf toadfish make mating calls, which may make them vulnerable to predation by dolphins such as bottlenoses; dolphin diets often include sound-producing fish, making up to 80% of their diet, approximately 13% of which are toadfish. ^[4] In response, gulf toadfish are able to suppress their calls when detecting dolphin; their cortisol levels were significantly elevated when exposed to dolphin calls, while the clicks produced by snapping shrimp were ignored as background noise. ^{[5] [4]}

Toxins

Gulf toadfish are commonly believed to be toxic/venomous, but this belief is untrue. While other members of the batrachoidid family (toadfishes) do have toxic excretions, the Gulf Toadfish does not. The purpose of these excretions is still unknown and, although it can have irritating effects on people and fish, it is not a toxin. ^[6]

Relation to humans

Angling

The Gulf toadfish is commonly considered a trash fish, rarely being eaten. They appear dangerous and slimy, so people refrain from eating them. They will eat anglers' baits readily and prevent them from catching game fish. They will usually eat chunks of bait, especially wide baits, such as cut squid or frozen fish.

They are widely disliked because they have a tendency to swallow hooks making them difficult to unhook. They also compete with resources for more desirable game fish and have few predators.

References

1. Collette, B.; Aiken, K.A. & Polanco Fernandez, A. (2015). "Opsanus beta". The IUCN Red List of Threatened Species . 2015: e.T190257A1946238. doi: 10.2305/IUCN.UK.2015-4.RLTS.T190257A1946238.en .
2. "WoRMS - World Register of Marine Species - Opsanus beta (Goode & Bean, 1880)". Marinespecies.org.
3. Smith, Lavett C. (1997). Tropical marine fishes: of teh Caribbean, the Gulf of Mexiko, florida, the Bahamas, and Bermuda. A chanticleer press edition. New York: Alfred A. Knopf. ISBN   978-0-679-44601-9.
4. Remage-Healey, Luke; P Nowacek, Douglas; H Bass, Andrew (2006). "Dolphin foraging sounds suppress calling and elevate stress hormone levels in a prey species, the Gulf toadfish". The Journal of Experimental Biology. 209 (22): 4444–4451. Bibcode:2006JExpB.209.4444R. doi:10.1242/jeb.02525. PMID   17079715.
5. "Fish Eavesdrop to Avoid Becoming Dinner". Livescience. 3 November 2006. Retrieved 2016-10-20.
6. "Structure and Function of the Axillary Organ of the Gulf Toadfish, Opsanus beta (Goode and Bean)" (PDF). Comp. Biochem. Physiol. 119A (1): 17–26. 1998. Retrieved 2022-03-21.