Manatee Anatomy - Save the Manatee Club

Manatee Anatomy FactsAlthough they feed in water, manatees excludemost of the water when they swallow, whichmakes the contents of their stomach relativelydry. Like terrestrial herbivores (plant eaters),manatees have large salivary glands (forlubrication and initial digestion of food).Like the horse, manatees are hind-gut digestersas opposed to fore-gut digesters (like the cow).This means that more of the digestive processesoccur further along the intestinal tract. It takesabout seven days for material to pass through themanatee’s digestive system.A manatee’s teeth are similar to the molars ofsome other mammals and are located in the backhalf of the lower and upper jaws. Manatee teethare unique in that they are replaced horizontally,as opposed to vertically as in most othermammals. Tooth replacement is continuous(polyphyodont) throughout their lives, as opposedto that of other mammals which replace a singleset of teeth once in a lifetime (diphyodont).The manatees blood is very important intransporting heat and regulating bodytemperature.Manatee lungs are unique—unlike other mammallungs that are positioned around the heart andextend backwards over the stomach and liver,manatee lungs are flattened and elongated. Thelungs extend horizontally along the back almostto the anus. The branching pattern of the bronchi(the primary air tubes) and blood vessels issimpler in manatees than in other mammalian lungs.Naris(nostril)NarisMouthEyeVibrissae(whiskers)BrainEarOpeningFlipper(Fore limb)NailsEsophagus(throat)TongueTrachea(wind-pipe)TeethMammary GlandlocationHeartCardiacGlandLiver(cut away)Scapula(shoulder blade)6 Cervical VertebraeElbowAxilla(‘arm’ pit)Umbilicus(belly button)Spleen Lung KidneyCecumStomachIntestinesFlukeAnusFemale Urogenital (U/G) OpeningMale U/G OpeningOvaryUrinary BladderAnusFemale U/G Opening16-19 Thoracic Vertebrae1-3 Lumbar Vertebrae23-27 Caudal VertebraeThe manatee swims with up and down (dorsoventral)motions of its body and fluke. This issimilar to the swimming motions of the cetaceans(dolphins and whales) but is unlike the side toside swimming motions of fish and seals.The muscles of the manatee have little of themyoglobin (muscle hemoglobin) that is typical ofthe muscles of other diving mammals—thismeans manatees cannot store as much oxygenas seals and dolphins, which is reflected in theirrelatively short (8-15 minute) and shallow (10-20feet) dives.Their ribs and other long bones lack marrowcavities, which produces a dense and relativelyheavy skeleton. Marrow, which produces redblood cells, is mostly restricted to the centra(bodies) of the vertebrae and possibly the sternum.Manatees do not have hind limbs. Their pelvicbones are vestiges of the more complexstructures of their ancestors. The pelvic vestigesare attachment sites for muscles.Manatees live in both fresh and salt water. Theirkidneys filter blood to control levels of salt and tomaintain water balance. The urinary bladderstores urine until it is advantageous to dump it intothe environment.The manatees’ mammary glands (milk glands)and teats (one per side) are located behind thefore limbs. The milk glands have no storage sacs(like cattle and goats) so manatee calves sucklefrequently at short intervals.The ribs of the manatee arch up to allow the Orbit (eye socket)lungs to be positioned much higher along the Mouthvertebral column than is found in most othermammals. The elongated lung distributes theMandiblebuoyant forces along more of the body than(lower jaw)would be possible in a more typically shaped lung HumerusSternum(thus helping the manatee to float horizontally).(breast-bone)This orientation also minimizes the pressuredifferences between different parts of the lung.RadiusUlnaOlecranon(elbow)RibsPelvicVestige9-13 ChevronsBonesManatees have relatively small brains whencompared to other mammals of their size. Theirbrains are very smooth, having few of the surface‘folds’ that are associated with higher intelligencein other mammals.For more manatee information,please visit our web site:www.MyFWC.comThe printing of this mini-poster was made possible through funding bythe Save the Manatee license plate and from Mr. Bill Crumpacker, whodonated funds to make sure the posters were available for students andfamilies. Manatee facts and graphics were supplied by SentielRommel of the FWC Marine Mammal Pathology Lab. The mini-posterdesign was created by Bonnie J. Abellera of the FWC ImperiledSpecies Management section.Feeding, touching and chasing wildlife are forms of harassment that mayput the animal in danger. Please keep your distance from all wildlife.To report an injured or dead manatee,or someone harassing a manatee,please call 1-888-404-FWCC (3922)Florida Fish and Wildlife Conservation CommissionDivision of Habitat and Species Conservation620 South Meridian Street, 6-ATallahassee, Florida 32399-1600(850) 922-4330RV: 05/05