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Monachus tropicalis (Gray 1850)

Order Carnivora : Family Phocidae

DESCRIPTION. The Caribbean monk seal was a relatively small seal, the upperparts nearly uniform brown, tinged with gray; sides paler; underparts pale yellow or yellowish white; soles and palms naked; pelage very short and stiff; nails on anterior digits well developed, on posterior digits rudimentary. Dental formula: I 2/2, C 1/1, Pm 4/4, M 1/1 × 2 = 32. External measurements: total length of males about 2.25 m; females slightly smaller. Weight, 70–140 kg.

Monachus tropicalis

DISTRIBUTION. Now extinct, the Caribbean monk seal was the only seal native to the Gulf of Mexico. They were tropically distributed but limited to the Gulf of Mexico coast, Yucatan Peninsula, western Caribbean Sea, the Greater and Lesser Antilles, the Bahamas, and the Florida Keys. Records from Texas include one sighting in 1932 and several instances of remains recovered from coastal archaeological sites. Monachus tropicalis probably became extinct by the mid-1950s.

SUBSPECIES. The Texas population was never assigned to a subspecies.

HABITS. Notwithstanding the fact that this seal has been known from the time of Columbus, no specimens reached museums until the middle of the twentieth century, when its numbers were already so depleted that it had become rather rare. Likewise, very little life history information is available.

These seals preferred sandy beaches for hauling-out grounds, such as the low, sandy islets making up the Triangle Keys west of Yucatan. While on land, they were sluggish and had no fear of humans, a trait that permitted their slaughter to the point of extinction. In former years they were used extensively as a source of oil.

The young apparently were born in early December, because several females killed in the Triangle Keys during that time had well-developed fetuses. No information is available on their food habits, but they probably ate fish and mollusks.

POPULATION STATUS. Extinct. This seal rarely occurred in Texas waters but once was common in the Gulf of Mexico to the south and east.

CONSERVATION STATUS. The IUCN lists the Caribbean Monk seal as extinct. It does not appear on any state or federal list.

REMARKS. Dale Rice of the National Marine Mammal Laboratory has asserted that none of the alleged sight records from Texas are credible, and Gerald Raun of the Welder Wildlife Foundation has suggested that specimens from archeological sites in Texas were probably traded from elsewhere.

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From The Mammals of Texas, Seventh Edition by David J. Schmidly and Robert D. Bradley, copyright © 1994, 2004, 2016.  Courtesy of the University of Texas Press.

Natural Science Research Laboratory