
Hunting is usually the first thing
that comes to peoples’ minds when considering threats to marine
mammals. Most people know that for centuries, marine mammals were
harvested for food, fur, and various other commercial goods.
Whaling began over 3,500 years
ago, and it progressed with technology to eventually become a
worldwide occupation before being greatly reduced by an
international ban in 1982. Almost all species of whale had been
hunted at some point in their history, leading to serious population
depletions for many species.
Although whales were hunted for
their meat, the most important item attained from the hunt was oil.
Baleen whale oil was used in margarine and other food products.
Sperm whale oil was used in special lubricants. In the 20th
century, whaling also became an important source of livestock food
and chemical products.
In 1946, the International Whaling
Commission (IWC) was set up to manage the hunting of whales in the
face of decreasing populations. This organization was originally
created to manage whales so they would always be available for
hunting. However, as it evolved this organization came experienced
internal conflict when the concerns of its scientific community were
pitted against commercial needs. In 1982, a ban on all commercial
whaling was passed by the IWC, with exceptions made only for native
cultures such as the Inuit of Northern Canada. This made whaling
for most nations a thing of the past. (Although today some
countries such as Norway and Japan continue to insist on the
resumption of commercial whaling.)
Since the discontinuation of
hunting, most whale species have been making a comeback. However,
given the very long life spans of these animals and their
exceedingly slow reproduction rates, most populations have yet to
fully recover.
Seals have also been hunted by man
since they were first discovered. They were large enough to provide
an abundance of food, small enough so no great risk was involved,
and largely available due to their population size and existence
near shore.
Seals supplied many products for
human use. Their meat provided food, their skin protection from the
elements, and their blubber light and warmth by burning in lamps.
Many cultures, such as the Arctic Inuit and Canoe Indians of South
America, developed cultures that depended upon these creatures for
survival.
Seal hunting changed from a native
practice to a commercial occupation in the early 18th
century. Harp seals were the first to be taken in vast herds.
Eared seals, such as the Northern Fur Seal, then also suffered a
drastic decrease in numbers due to this practice. The Antarctic Fur
seal was almost driven to extinction by commercial hunting.
Walruses also suffered due to hunting for their tusks, oils, and
skins. As with whales, since the discontinuation of most hunting,
many populations (like that of the Antarctic Fur Seal) have made
excellent recoveries. However, some population have yet to fully
rebound to their previous levels.
Although there are now laws in
specific nations (such as the US Marine Mammal Act) that protect
seals, there are no treaties protecting them worldwide and they
continue to be hunted for food and fur in some places.
Sea Otters were also extensively
hunted in the past for their specialized coats. In fact, they were
so popular that their populations also almost went extinct in the
early 20th century. Fortunately, however, in 1911 an
international agreement was created that protected the sea otter
from further commercial hunting. Today this animal survives and
there are efforts underway by humans to reestablish the sea otter
into its entire former range.