what is trawlers nets type

Trawler nets are specialized Fishing Nets used by trawlers, which are boats designed to pull nets through the water to catch fish. These nets come in various types and configurations depending on the target species, fishing method, and environmental conditions. Here are the main types of trawler nets:

1. **Bottom Trawl Nets:**

   - **Description:** These nets are designed to operate on or near the seabed.

   - **Structure:** The net has a large, cone-shaped body with wings extending from the sides, leading to a narrow codend (the end part of the net where fish are collected).

   - **Applications:** Used to catch groundfish and demersal species like cod, haddock, flounder, and shrimp.

   - **Features:** Equipped with heavy weights and rollers to keep the net on the sea floor and sometimes include tickler chains to stir up fish.

2. **Midwater (Pelagic) Trawl Nets:**

   - **Description:** These nets are towed through the water column, above the seabed.

   - **Structure:** Similar to bottom trawls but lighter and designed to stay in midwater.

   - **Applications:** Used to catch pelagic species like herring, mackerel, and sardines.

   - **Features:** Designed to maintain a stable position at various depths, often using floats and otter boards to keep the net open.

3. **Beam Trawl Nets:**

   - **Description:** This type of net is held open by a rigid beam.

   - **Structure:** The beam is attached to two large shoes or skids that slide along the seabed.

   - **Applications:** Commonly used for flatfish and shrimp.

   - **Features:** Simple design, effective for targeting species that live on or near the seabed.

 4. **Pair Trawl Nets:**

   - **Description:** Involves two boats towing a single net.

   - **Structure:** The net is typically large and can be towed at greater speeds, with the boats maintaining a set distance to keep the net open.

   - **Applications:** Used for both pelagic and demersal species, depending on the design of the net.

   - **Features:** Requires coordination between two vessels, which can make it more complex but allows for larger catches.

5. **Otter Trawl Nets:**

   - **Description:** These nets use otter boards (large, flat boards) to keep the net open horizontally.

   - **Structure:** The net is spread by the otter boards that are attached to the wings of the net.

   - **Applications:** Versatile and used for a wide range of species, both pelagic and demersal.

   - **Features:** The otter boards create a wide opening, allowing for efficient capture of fish.

 6. **Danish Seine Nets (Anchor Seine):**

   - **Description:** A type of trawling net that is used in conjunction with a seine method, where the net encircles the fish.

   - **Structure:** The net is laid out in a circle and then drawn together to capture the fish.

   - **Applications:** Effective for catching demersal species.

   - **Features:** Involves the use of long ropes to herd fish into the net.

7. **Fly-shooting Trawl Nets:**

   - **Description:** Similar to Danish seining, but typically involves more active herding of fish.

   - **Structure:** Uses longer ropes and larger nets, often with the boat maneuvering to encircle fish.

   - **Applications:** Used for species that form dense schools or are spread out over a large area.

   - **Features:** Requires skillful boat handling and precise net deployment.

The type of trawler net chosen depends on various factors, including the target fish species, fishing depth, and environmental conditions. Each type has its specific design and operational characteristics to maximize efficiency and effectiveness in capturing fish while minimizing environmental impact and bycatch.