|Rays and skates
are similar species that are closely related to sharks.
Collectively, they are known as batoids. Like sharks,
their skeletons are made of cartilage instead of bones.
Cartilaginous fish belong to the class of fishes known
Most rays are kite-shaped with streamlined tails
that may have one or more poisonous barbs or spines.
In contrast, skate tails are fleshier and heavier,
and have small fins. In general, skates commonly
found in North American waters have elongated noses.
Size is another way to differentiate rays from
their skate cousins. Rays can grow to tremendously
large sizes. For example, the manta ray (Manta
birostris) can reach a width of 22 feet, weighing
several tons. The five species of skates commonly
found in North Carolina waters range in size from
16 inches to 5 feet in length.
Rays and skates use different mechanisms to defend
themselves, too. The stinging spine on the rays
tail is an effective weapon against predators. The
edges of the spine are serrated so that once driven
into a victim it is very difficult to remove without
creating more damage. A thin skin covers the entire
structure, and when ruptured, venom is released
into the victim. Since skates do not have stinging
spines, they rely on large thorns on their backs
and tails to deter predators.
Skates and rays differ from each other in the way
they give birth. All skates lay eggs, which are
leathery cases very similar to shark egg capsules.
These cases sometimes wash up on beaches and are
called mermaids purses. Rays, on the other
hand, give birth to live young.
Gliders: The cownose
ray is one of several species found off the North
Carolina Coast. The cownose is one of a few
rays that will jump out of the water, landing with
a loud "smack". Researchers believe
this behavior might be a territorial display.
Southern Stingray is
one of the most common rays found along our shore.
This ray often lies buried in the sand so that only
its eyes and spiracles (nostrils) are exposed.
These differences determine how skates and rays
are categorized and classified scientifically. Despite
the obvious distinctions, classifications of these
unique animals are often the subject of debate among
researchers. It doesnt help that sometimes
"ray" is used as a catchall category that
encompasses both ray and skate species. However,
according to the International
Code of Zoological Nomenclature, the majority
of rays belong to the scientific Order Myliobatiformes
with one exception, the electric rays, which
belong to the Order Torpediniformes. Skates are
members of completely separate order known as Rajiformes.
In all, there are seven main families of rays in
the Order Myliobatiformes, including stingrays,
butterfly rays, devil rays, eagle rays, river rays,
round stingrays and six-gill rays. Some of the individual
species common off the North Carolina coast are
the smooth butterfly ray (Gymnura micura),
the spotted eagle ray (Aetobatus narinari),
the cownose ray (Rhinoptera bonasus) and
the southern stingray (Dasyatis americana).
There is only one family of skates, the family
Rajidae. Skates common to North Carolina include
the clearnose skate (Raja eglanteria), the
winter skate (Raja ocellata), the little
skate (Raja erinacea), and the barndoor skate
First Aid for Stingray Injuries
According to the Diver's
Alert Network, most stingray injuries occur
when an unseen stingray is stepped upon. The
ray, in an effort to defend itself, injects its
spine into the victim, causing a serious puncture
wound. A sheath covers the entire spine, and
when ruptured, venom is released into the victim.
Stingray venom can cause the following reactions:
- Pain which may last several days
- Nausea and Vomiting
- Appetite Loss
- Muscular Cramps, Tremor and Paralysis
Because removal of a stingray spine can often make
the wound worse, it is best to seek immediate medical
If you are stung by a stingray and cannot get immediate
- Irrigate the wound to remove surface venom.
- Carefully try to remove any portions of the
spine and sheath that remain in the wound.
It may be best to let a doctor attempt this.
- Immerse the area in hot water (113 F) for 30
to 90 minutes or until pain is relieved.
- Seek medical attention as soon as possible.