Gear Comparison and Specifications

A project log for 2020 HDP Dream Team: Conservation X Labs

The 2020 HDP Dream Teams are participating in a two month engineering sprint to address their nonprofit partner. Follow their journey here.

Erin RobotGrrlErin RobotGrrl 07/13/2020 at 01:470 Comments

While narrowing in on our project scope, we were trying to determine the gear type should we specifically design for, and / or test with. We learned from @Oluwatobi Oyinlola  ’s interview with a fisher that they primarily use passive gear.

When comparing two types of passive gear: traps & pots and longlines, they are diametrically opposed on value vs quantity of landings.

This makes for a dilemma in choosing a gear type as a prime candidate for testing and designing! Read on for more information, and gear distance specifications.

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In our meeting last week, @Giovanni shared some thoughts towards how to go about deciding: whatever gets us closer to testing a solution the fastest. Sometimes this can mean starting with a high-end solution to appeal to that market, then spreading it out to the more challenging areas. 

There is also the option that we could try to make a generic solution across the different gear. 


Here is a data sample from the Canada Department of Fisheries & Oceans.


Seafisheries landed value by province, 2018

All Groundfish (eg, halibut and cod) total = 410,344

Lobster total = 1,419,651

Crab total = 748,183

Lobster and crab have the greatest value

[source (Accessed July 7)]


Seafisheries landed quantity by province, 2018

All Groundfish total = 228,239

Lobster total = 97,381

Crab total = 67,284

Groundfish has the greater quantity

[source (Accessed July 7)]


Looking at data from the high seas (also known as international waters) shows the vast usage of longlines as well:

[source (Accessed July 7)]


The most common gear reported to the Global Ghost Gear Initiative are nets, and Ghost Nets Australia has also found the majority of gear to be nets. [source: GNA Annual Report 2012 (Accessed July 12)]

[source (Accessed July 12)]

Gear Distances

Traps & pots

Depending on the type of vessel used, there are a variety of traps & pots configurations. Here is a sampling of a few - minimum, medium, and maximum. The diagrams are from Gulf of Maine’s Lobster Gear Configurations [source (Accessed July 12)], however I replaced the Fathom unit scale with metres.

[source (Accessed July 12)]

[source (Accessed July 12)]

[source (Accessed July 12)]

For general interest, a toggle is “a small float, generally less than 5 inches in diameter, deployed on a short gangion off the buoy line to prevent gear from getting snagged on the bottom” [source (Accessed July 12)]


[source (Accessed July 12)]

[source (Accessed July 12)]

To Be Continued…

We haven’t decided yet. As we gather more information from fishers and our stakeholder, it will help the choice. Stay tuned!