exam 3 Flashcards
why are weddell seals easy to study/how do we study them
They like to be on the fast ice/beaches close to land so they are easily observable. They are curious so they are easily approachable. They make open holes in the ice that they use for breathing/entryway to the sea to get prey. They keep the holes open with their procumbent incisors. We can send instruments down the holes.
weddell seals appearance and life history
They have a muddled appearance (dark grey top, lighter bottom), and are about 2.5 m long. The females are longer than the males. They give birth in early summer (October) and nurse their pups for 6-7 weeks. They’re more spread out than elephant seals. Enemies include leopard seals and orcas.
history of exploitation, fur seals, elephants seals, and whales
Fur seals were first exploited for their pelts. Next, elephant seals were exploited for their blubber (specifically the oil in it). Whales were then targeted after the other populations were depleted, for their blubber.
how was sealing started and spread
Sealing began on the Falkland Islands in 1765 and spread to South Georgia in 1786. In 1775, 13,000 fur seal skins were taken from Falkland by one ship.
how many seal skins were taken between 1793 and 1807?
3.2 million
what happened when sealing spread to the south shetland islands and antarctic peninsula
operations moved here in 1819 and 300,000 fur seal skins were taken from the AP in 4 years
when and why did sealing end
in 1822 sources were depleted and they moved on to elephant seal blubber
when did whaling began
in the mid 1800’s when other populations were depleated
methods and history of whaling
- people would row out and hunt the whales with hand spear one by one.
- whaling stations were developed and allowed them to hunt right around the station/process them on land.
- The swivel canon was invented and allowed whalers to kill more whales faster, but they still needed to be processed on land.
- factory ships allowed for whales to be killed and processed at sea.
fencing platforms
platforms on the whaling stations where the whales were processed. Long knives were used to cut out chunks of blubber. The blubber was then boiled to extract the oil.
how was the blubber though to be exposed of after extracting the oil
A slope in the back of Grytviken was thought to be used to drop blubbler sections off.
swivel harpoon canons
This took whaling from being done with hand spears to being able to kill the whales from the ships. It was invented in 1865 by Svend Foyn. The guns not only contained gun powder on the ships, but also in the gun head which exploded in the whale instantly killing it.
Svend Foyn
Invented the swivel gun in 1865 which increased exploitation of the whales.
Grytiviken
Established on South Georgia, it was the first whaling station (1904). It increased the rate of exploitation.
how many humpbacks were taken from right around Grytiviken station in the first few years
6,000
In the first decade how many whales were taken
1700 blue whales, 4800 finback, and 22000 humpbacks were taken
What was baleen from the whales used in
corsets
when was the station Grytiviken abandoned
when factory ships were invented (ghost towns today)
deception island and whalers bay
Norweigen whaling station from 1906-1931 in whalers bay on deception island. It got affected by volcanic eruption that caused people to leave. Prime location because of the inlet/protection it provided. There’s also warmer water due to the volcanic vents.
factory ships
Allowed whales to be killed and processed at sea, which increased exploitation.
when were factory ships first invented
in 1925, by 1930 there were 41
how much did whale intake increase
from 14000 to 40000
what happened after ww2
whaling continued. blue whales, then fin, sei, and minke were depleted (largest–>smallest)
when did whaling end
most ended in 1960 as stocks depleted, but illegal whaling still takes place