Transcript VII. Overfishing - Crestwood Local Schools

VII. Overfishing
A. Harvesting Fish
1. Over half of all marine species are fully
exploited
2. 25% are over-exploited and are moving
toward extinction
3. These will lead to collapse of fisheries
a. If continued at current rates will
collapse by 2048
B. Factors Affecting
1. Overharvesting is just one factor
a. Includes hunting, fishing, and
collecting
2. Eutrophication and hypoxia damaging
populations as well
3. Low populations of grazing marine
animals have allowed overgrowth of grass
beds
a. Breeding ground for disease
causing bacteria
4. Industrialization of fishing allows larger
catches
a. Driftnets float near surface trapping
large schools of fish
b. Long-lines- hooks and baits hang
from floating line and catch predatory
fishes
c. Bottom-trawling- nets drag bottom
trapping benthic fishes
d. These methods overcatch valuable
species as well as non-target
organisms damaging the food web
e. Also disrupt habitat
C. Outcomes
1. Able to makes declines by traveling
farther and fishing deeper
2. We target similar species or younger fish
3. We can affect by our choices of marine
products
a. Must package how and where caught
4. Aquacultures have potential to lessen
impact if done correctly