88 Sharks: The Animal Answer Guide
Spotted Eagle Rays in the Bahamas move offshore in early summer and re-
turn to shallow reef areas by late summer. Manta ray behavior is slowly be-
ing revealed; they too migrate. For example, Giant Mantas migrate across
the Indian Ocean from Mozambique to the Maldives, a distance of 1,120
km (700 miles) in two months. Cownose Rays are among the better-known
species because they migrate in large numbers, often near the surface, and
are therefore visible from boats and planes. Cownose Rays move seasonally
along the U.S. Atlantic coast, going north in the late spring and south in
late fall between Virginia and Florida and even as far as between the Chesa-
peake Bay and Brazil.
A few studies have looked at whether skates migrate. Because they are
small animals that lie on the bottom in deep, cool water, we wouldn’t ex-
pect them to be highly mobile, and many aren’t. A 20-year study of Thorny
Skates off Newfoundland found that most skates didn’t undergo obvious
seasonal migrations in any particular direction but instead moved slowly
from their tagging location. Many skates moved less than 30 miles (48 km),
and most less than 60 miles (96 km), even after many years. One moved
less than 5 miles (8 km) in 14 years. Among five skate species that occur
along the Atlantic coast of the United States (Thorny, Smooth, Clearnose,
Little, and Winter), Thorny and Clearnose skates did not migrate, whereas
Clearnose, Little, and Winter skates undertook apparent seasonal migra-
tions. Clearnose Skates move both north and south as much as 580 km (360
miles), and inshore and offshore as much as 120 km (74 miles). The inshore
movement in early spring is probably a spawning migration. Some Lit-
tle Skates move inshore in the spring and offshore in autumn and winter.
Winter Skates are the strongest migrators, although again not all individu-
als move. In winter and spring, Winter Skates move south or offshore from
an area in the Gulf of Maine, some animals traveling as much as 940 km
(584 miles). But compared with their shark and ray relatives, these skates
are weak migrators.
The movements of chimaeras are poorly understood. The Australian
Ghostfish of Australia and New Zealand normally occurs in fairly deep wa-
ter, down to 200 m (656 ft). Reproductively active animals move into shal-
low bays to lay eggs during their summer and autumn spawning season.
They move back offshore to deep water in winter and spring. Egg cases of
the Elephantfish, Callorhinchus callorynchus, have also been found in shal-
low water, suggesting that this chimaera also moves inshore to spawn. The
Spotted Ratfish is a vertical migrator, moving up from deeper water in the
day to shallower water at night. Aside from these three, we can’t say much
about chimaera movements.
Many sharks move up and down periodically or irregularly. Although
the distances traveled are less spectacular than transoceanic movements,
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