Marine Fisheries Quiz 3

Purse Seine

• Reduction fisheries

• Salmon and Tuna

• FAD

• Bunt: Fine mesh area in the middle

Lampara Net

Small and light, similar to a purse seine but open on the bottom. (Squid, Sardine)

Trawls

Used for Demersal species. (Shrimp, Cod)

Expensive due to high horsepower from net drag.

Types of Trawls

Otter, Beam, Skimmer, Butterfly, Rockhopper.

Trawl Parts

Towing Warps, Headline, Groundline, Codend.

Side Trawl

Original layout, side deployment and retrieval, effective but dangerous in wind.

Stern Trawl

Effective and safer in wind.

Rockhopper Trawl Problems

• Balancing Technology

• Fishing Power

• Efficiency

• Social Value

• Habitat Impacts

Mid-Water Trawl

Adjustable height with sonar to find fish schools. (Pollock, Mackerel)

Pelagic

Middle water column.

Epibenthic

Middle and Bottom water column.

Infaunal

Along ocean floor.

Trawling Issues

• zoobenthos composition and function

• re-suspension of nutrients and toxins

• change in O2 conditions

Dredge

• Epifaunal and infaunal species.

• Tongs and rakes

Hydro-Dredge

Move sediment to release organisms.

Gill Net

• Passive

• Strike Net: Striped Mullet

• Lots of bycatch

• Monofilament is less visible

Shark Fin Sales Elimination Act 2021

Illegal to possess, sell, or buy product containing shark fins.

Pound Net

Effective for nearshore migratory and mobile stocks. (Mullet, Mackerel)

Longline

Surface or bottom fishing using gangions. (Billfish, Halibut)

Pots

Invertebrate cages. (Crabs)

Pot Considerations

• Entrance

• Escape Vents (cull rings)

• Biodegradable Panels

• Ghost Fishing

• Gear Conflicts

Depensation

Effect on a population that decreases the breeding population, production, and survival of eggs and offspring. (Peruvian Anchoveta)

Top 5 Countries in Harvest

1. China

2. Japan

3. India

4. Chile

5. Indonesia

Commercial Group Harvests

1. Herring, Sardine, Anchovy

2. Carp, Barbel, Cyprinid

3. Cod, Hake, Haddock

4. Tuna, Bonitos, Billfish

Commercial Finfish Harvests

1. Walleye Pollock

2. Gulf Menhaden

3. Atlantic Menhaden

4. Pacific Hake

5. Pink Salmon

6. Pacific Cod

7. Sockeye Salmon (High Value)

8. Yellowfin Sole

9. Pacific Ocean Perch

10. Atka Mackerel

Stock Value Top 2 FIsh

1. Bluefin Tuna

2. Bigeye Tuna

World Invertebrate Harvests

1. Shrimp

2. Clams

3. Oysters

4. Squid/Octopus

5. Scallops

6. Crabs

2019 Harvest

-Finfish 8.32b lbs - $2.48b

-Non-Fish 0.99b lbs - $2.98b

U.S. Invertebrate Harvests

1. Gulf Shrimp

2. Blue Crab

3. American Lobster

4. Pacific Squid

5. Dungeness Crab

6. Atlantic Squid

7. Sea Scallop

8. Pacific Shrimp

9. Surf Clam

Tanner (Snow) Crab

Not adapted to high harvest levels in the 1990s.

Stock Value Top 2 Invertebrates

1. Manila Clam

2. Geoduck Clam

Fluctuations in Fisheries

• Common in r-selected species

• Significant management problems due to unpredictability

• Economic hardship for fishers

• Need for modeling to understand interactions between recruitment, stock size, and environment.

Top 5 States for Weight

1. AK (5 Billion)

2. LA

3. WA

4. OK

5. VA

Top 5 State for Value

1. AK

2. MA

3. ME

4. LA

5. VA

Top States in Catch and Release

1. FL (Strict Regulations)

2. NC

3. NY

4. VA

5. NJ

Barotrauma

Mortality due to atmospheric pressure.

Physostomous

Fish bladder that is connected to the stomach.

Physoclistous

Fish bladder that is not connected to the stomach.

Recreational Fishing Harvests

1. Tuna/Mackerel

2. Drums

3. Porgies

4. Snapper

5. Temperate Bass

6. Bluefish

7. Dolphinfish

8. Jacks