Delaware State Mammal
Gray Seal (common name) Halichoerus grypus (scientific name) Overview Gray seals live along the Canadian and U.S. east coast, mostly in the north but as far south as Virginia, and are residents of Delaware’s shores. As seals go, gray seals are medium-sized, and differ from common seals by having a straight profile, more widely spaced nostrils, and fewer spots. The gray seal’s scientific name,Halichoerus grypus, means "hooked-nosed sea pig," and refers to its large, wide-set nostrils. Close-up STATUS Unofficial ALSO KNOWN AS Grey seal, horsehead PHYSICAL DETAILS In spite of its name, the gray seal’s color varies considerably. Females are usually range from silvery gray to brown with darker spots and are generally lighter colored than males. Females’ coats are even lighter on their chests and on the undersides of their bodies. Male gray seals normally range from dark grayish brown to black, with pale patches and lighter scars around their necks. Most gray seals, particularly the males, have a noticeably long nose with wide nostrils, the animal’s most distinguishing feature.     Males Females Size 8–11 ft (2.5–3.3 m) long 5.25–6.5 ft (1.6–2.0 m) long Weight 650–775 lbs (300–350 kg); maximum over 880 lbs (400 kg) 330–440 lbs (150–200 kg); maximum over 550 lbs (250 kg) LIFESPAN Maximum 46 years for a female, 29 years for a male; average 35 years for a female, 25 years for a male. HABITAT Cool to cold coastal areas, including rocky coasts, unpopulated islands, and icebergs. Range: Coastal Great Britain and Ireland, Faroe Islands, Iceland, the Baltic coast, coastal Canada, and south as far as Virginia, isolated populations on the French, Dutch, and German coasts. Conservation: Least Concern (LC). The U.S. gray seal population is currently increasing. Until 1962, American populations were diminishing because of hunting. With the 1972 Marine Mammal Protection Act, populations began to rebound and are becoming more common in the southern part of their range. BEHAVIOR In the U.S., gray seal pups are born in the winter on ice or land. At birth, they have soft white fur, but they shed this by the time they are a month old. Once their waterproof adult coat has grown in, they learn to fish and quickly become independent. Baby gray seals nurse for only 15 to 18 days, and less if they are born on ice, but they gain 2.5 to 4.5 pounds (1.2 to 2 kg) per day while they nurse. They lose weight again once they’re weaned, before they learn to fish for themselves. Male gray seals mature at four to six years but usually start breeding when they are nine to 10 years old. They don’t normally come to land until after the first pups are born. In breeding season, males spend much of their time out of the water, and they go without eating. Some return to sea for a couple of days at a time, but others do not. Adult males stay on shore an average of 36 days, and as long as 57 days, so they lose a substantial amount of weight during breeding season. Male gray seals stay near a group of females but don’t define or defend a particular territory. Males often mate with up to 10 females, though in sparsely populated icy or sandy areas they may only be able to find one mate. Females are mature when they are three to five years old. They come to shore shortly before giving birth and stay there, fasting, until their pups are weaned and they have mated, usually about three weeks. Mating can occur on land or ice or in water. Because they are lactating at the same time, females tend to lose more weight than males during the breeding and fasting period. Gray seals tend to stay in a particular area throughout the year, though they can travel more than a hundred kilometers off shore for short periods to search for food when necessary. Seals searching for food usually look for gravel or coarse sand seabeds, the habitat of their favorite food, sand eels. Usually, though, they forage locally and make routine rounds to find food. Gray seals in the U.S. and Canada molt in May and June. Top land speed recorded: 35 mph (56 kph) DIET Fish, sand eel, and skate are the most common sources of food. Diet varies by location, and individual gray seals can show strong preferences for a particular food. Less common food sources include crustaceans, mollusks, and even sea birds.  OFFSPRING Breeding interval: Annual Birthing period: January to February Average litter size: 1 pup Size at birth: 40 pounds (18 kg) TRIVIA Gray seals can dive as deep as 980 feet (300 m) and stay submerged for as long as 20 minutes. Sharks and killer whales are American gray seals’ most common predators. Gray seals are individualistic and have their own favorite foods, land sites, feeding locations, and hunting techniques.
	Click to enlarge an image Grey Seal with Pup Close-up of Grey Seal Young Grey Seal CLASSIFICATION Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Carnivora Suborder: Caniformia Superfamily: Pinnipedia Family: Phocidae Genus: Halichoerus Species: H. grypus
	Data Source: U.S. Fish and Wildlife Service Author: World Trade Press

Delaware State Mammal
Horseshoe Crab (common name) Limulus polyphemus (scientific name) Overview Horseshoe crabs are sometimes described as living fossils because they evolved 360 million years ago and haven’t changed much since. They lived in shallow coastal waters before dinosaurs. Although this creature is commonly called a crab, the horseshoe crab, like the lobster, is actually more closely related to a spider. A horseshoe crab is valuable not only for its ancient biology, but as a link in the food chain, since its eggs are a source of food for shore birds. Close-up STATUS Official State Marine Animal ALSO KNOWN AS King crab, horsefoot, saucepan, helmet crab PHYSICAL DETAILS The front of a horseshoe crab’s body is a domed, horseshoe-shaped, green-brown shell, with six pairs of claws on the underside. Its mouth is also on the underside of the shell. The front-most pair of claws is used for eating. A horseshoe crab has 10 eyes, some of which serve different purposes. Two compound eyes are visible on top of its dome, important because they’re used to locate mates. It has five more eyes on top of its dome, one immediately behind each compound eye, and three at the front. These sense the sun’s ultraviolet light as well as moonlight. A horseshoe crab has two eyes on the underside of its shell, and photoreceptors in its long, spine-like tail. In the wild, organisms including algae, mollusks, barnacles, and flatworms sometimes attach themselves to the horseshoe crab’s rounded shell and live there, without harming the crab.     Males Females Size head to tail tip, 16–20 in (40–50 cm) head to tail tip, 22–24 in (55–60 cm) Weight 10–12 pounds (4–5 kg) 11–16 pounds (4–7 kg) LIFESPAN Up to 20 years HABITAT Sheltered beaches and nearby shallow waters of coastal bays with sandy or muddy bottoms. Range: The U.S. Atlantic coast from the Gulf of Mexico to Maine. Conservation Status: Near Threatened (NT). Illegal harvesting and habitat destruction have reduced numbers substantially in some areas. In some places, horseshoe crabs are used as bait. BEHAVIOR A horseshoe crab is active in daylight hours, either resting in shallow water or plowing through sand foraging for food. In late spring, a male horseshoe moves toward the beach to look for mates. Most activity takes place within a few days of the new and full moons and late day spring tides. A male locates females partly by sight and partly by sensing chemicals secreted by the females. The female, meanwhile, digs a nest between the high tide line and the low tide line and deposits her eggs, up to 4,000 at a time and perhaps 30,000 per nest. Males fertilize the eggs as they’re being laid or shortly afterward. Each female builds three nests per season. Eggs hatch about 14 days later. New horseshoe crabs look like tiny adults except that their tails are not yet visible. Not long after hatching, young horseshoes come out of the sand and into water, usually at high tide. Once in the water, they dig themselves into the sand and stay there for about a year. Once the crab molts for the first time, it acquires a tail and starts to feed. A young crab molts a few times a year for the first three years, and then once a year after that until it is 11 years old. At that age, it no longer molts and begins to mate. DIET Shellfish and sea worms including clams, annelid worms, mollusks, and benthic invertebrates.  OFFSPRING Breeding interval: Annual Birthing period: May to June Average litter size: 90,000 eggs Size at birth: 1.12–.20 in (3-5 mm) TRIVIA A horseshoe crab has no jaws, so it must crush its food with its legs before pushing little pieces into its mouth. Horseshoe crab blood clots in the presence of some bacteria, so it’s often used to test medicines for contamination. Delaware chose the horseshoe crab as the state’s marine animal on June 25, 2002.
	Click to enlarge an image Horseshoe Crab Spawning Horseshoe Crabs Underside of Horseshoe Crab CLASSIFICATION Kingdom: Animalia Phylum: Arthropoda Subphylum: Chelicerata Class: Merostomata Order: Xiphosura Suborder: Caniformia Family: Limulidae Genus: Limus Species: L. polyphemu
	Data Source: U.S. Fish and Wildlife Service Author: World Trade Press