Florida Manatees

Florida Manatees B I O L O G Y, B E H A V I O R , A N D C O N S E R V A T I O N

John E. Reynolds III

Photographs by Wayne Lynch

FLORIDA MANATEES BIOLOGY, BEHAVIOR, AND CONSERVATION JOHN E. REYNOLDS III photographs by WAYNE LYNCH

M

A photographic journey into the secret world of Florida’s beloved manatee.

anatees, the gentle giants of Florida’s lagoons and coastal habitats, bring a smile to almost every face that spies one. As manatees dip and roll through the water, crowds gather to watch them feed on their favorite food, aquatic vegetation.

Sometimes congregating by the hundreds, other times at ease resting or feeding alone, these sea cows provide anyone interested in nature with hours of tranquil pleasure.

Having survived for eons, today’s manatees are under constant threat because of our rapidly swelling human population. Their habitats are often devastated by development and pollution. The slow-moving manatees also live at the mercy of chance, for they occupy waters filled with fast-moving boats. For manatees, boat propellers are spinning razor blades, a new form of predator from which they have no protection. Boat speed limits have been put in place to protect manatees, but there is a constant push to lift them so that people can once again zip across manatee habitats. For this reason, manatees are often a subject of controversies that pit their lives against the rights of boat owners.

In this book, manatee expert John E. Reynolds and famed photographer Wayne Lynch join forces to reveal the clearest picture of manatees ever published. Florida Manatees is a song for the manatee, a celebration of the lives of these majestic creatures. Reynolds’ concise, informative text reveals what is known about manatees while Lynch’s beautiful photographs instantly demonstrate how special these “potatoes with whiskers” really are. By promoting an appreciation of manatees, the book hopes to ensure a future in which Floridians will continue to enjoy the sirenian inhabitants of the state.

Included in this book: •

how manatees first came to Florida waters and how early human settlers regarded them

•

how manatees fit into the ecosystems of Florida

•

what and how much manatees eat

•

how manatees behave and communicate with one another

•

why manatees look the way they do

•

why manatees have whiskers

•

how manatee mothers feed their young and much more

John E. Reynolds III is the senior scientist at Mote Marine Laboratory’s Manatee Research Program and the former chair of the US Marine Mammal Commission. He is the coeditor of Marine Mammal Research: Conservation beyond Crisis and the coauthor of Mysterious Manatees. Wayne Lynch is a renowned and widely published professional wild life photographer.

He is the author of Owls of the United States and Canada: A Complete Guide to Their Biology and Behavior and the coauthor of Penguins: The Animal Answer Guide.

4 The Stuff of Myths and Legends Given the nearshore and riverine habitats occupied by manatees, along with the edible and other products they provided for coastal communities in the prehistoric and more recent past, it is not surprising that manatees and their harvest became the stuff of myths and legends. Some of the traditional, long-standing perspectives remain, especially in subsistence communities, but in recent years new perceptions—and misperceptions—have arisen. Although it has been common for humans to focus on ways in which manatees can be used for or be useful to human enterprises, a new ethic has started to arise that highlights ways in which people and manatees can coexist, to the benefit of both. This chapter explores a range of examples to illustrate human values and perceptions toward Florida manatees and other sirenians.

It is clear that for most of the history of manatee and dugong interactions with people, the former two species were viewed primarily as sources of meat and other products for the latter. Subsistence-based societies generally maintain their cultural values through an oral, rather than a written tradition, so it is not known exactly how long people have harvested manatees and other sirenians. It is revealing, however, to consider that the biblical Ark of the Covenant has been suggested to © 2017 Johns Hopkins University Press UNCORRECTED PROOF Do not quote for publication until verified with finished book.

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Florida Manatees 40

In addition to the up-and-down motion of its fluke, the flippers of a manatee are unexpectedly flexible.

have been bound in a covering of dugong hide. In Florida, the harvest of manatees has been documented from digs that have occurred since the Paleo-Indian period (8500–6000 BC), coinciding with the first known occupation of the state by aboriginal indians. Dugong hunting in the Torres Strait (between Australia and Papua New Guinea) has been documented to have occurred for some 4,000 years, and one site in the strait (on Mabuiag Island) contains the remains of an astounding 10,000–11,000 dugongs, harvested over a 300-year period (dating from around AD 1600 to AD 1900). Clearly, humans and sirenians have a long relationship, from which the former derived substantial benefits.

Despite some of these remarkable harvest quantities, the impacts of subsistence-level hunting usually reflect, to some extent, the size of the human population when the harvests occurred. At the time Europeans arrived in Florida (about AD 1500), around 25,000 aboriginal indians commonly are estimated to have been in the state. The taking of a large and powerful manatee represented quite a task, and it is uncertain what sort of impact these indians had on the population of manatees at that

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Behavior and Ecology 61

in their species, but they also have individually distinctive signature vocalizations, which allow different manatees to recognize one another acoustically. Given the limitations of using vision underwater, acoustics provide the most important means of communication and threat detection for manatees.

Manatees in general, and especially females with calves, mouth and touch one another frequently. In addition, manatees exhibit play behavior, such as body surfing and follow the leader. Alone and in groups, manatees exhibit considerable curiosity and often mouth or otherwise interact with objects they find in their environment. This extends to human divers, with whom manatees may engage by clutching a diver’s legs and gently rolling underwater.

When manatees travel from one location to another, they often travel single file, but calves swim next to their mothers, in part for energetic reasons, since the drag they experience moving forward is reduced when they are positioned closely adjacent to the rear part of her body.

Manatees are powerful swimmers, capable of moving in bursts in excess of 20 miles per hour and of covering more than 50 miles in a day. As manatees migrate long distances to seek warm-water refuges or other resources, they tend to stop at predictable locations along the Atlantic or Gulf Coasts or the Intracoastal Waterway. The sensory mechanisms they use to navigate over long distances and select stopping points are not known, but cognition and communication expert Gordon Bauer and I have proposed that taste may be important (as it is for species

In clear water, over a sandy bottom, it is especially easy to observe the behavior of manatees, alone or in social groups. Not surprisingly, the best study of manatee behavioral ecology was conducted at the aptly named Crystal River.

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Florida Manatees 62

The close relationship between a female manatee and her calf is apparent in a number of ways, including a lot of touching, vocalizing, and even playing.

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Publication date: April, 2017 160 pages 9 x 11 141 color photos 978-1-4214-2191-9 $39.95 £26.00 hc

Also available as an e-book

FLORIDA MANATEES BIOLOGY, BEHAVIOR, AND CONSERVATION JOHN E. REYNOLDS III photographs by WAYNE LYNCH

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