Looking for something to do on World Ocean’s Day? We have added a new mission to Digital Fishers for the curious citizen scientist on “Trawling, thornyhead rockfish & deep-sea ecosystems.”
The last mission on “Trawling Impacts on Deep-Sea Ecosystems” resulted in 106 visits from the United States, Canada, France, and Belgium. Over the past 4 weeks, you have added over 3000 annotations to the database. Thank you to all who participated. We will post some of the findings after we have had a chance to review them.
Below is the new mission on Digital Fishers. In theses video clips, there is a huge variety of interesting marine life to see and annotate.
Trawling, thornyhead rockfish & deep-sea ecosystems: Mid-Continental Slope off Vancouver Island, BC
Bottom trawling is an industrial fishing method where a large weighted net is dragged along the seafloor, over long distances. On the mid-Continental Slope, the main target species for bottom trawling fisheries are thornyhead rockfish. These deep sea rockfish may be particularly vulnerable to overfishing because of their slow growth rate and long lifespan, possibly more than 100 years. Over the last eight years there has been a 50% decline in thornyhead catch per unit effort.
Unlike other rockfish, thornyheads are not found in schools but are distributed over wide areas of soft bottom sediment. With increasing fishing capacity, bottom-trawling activities are conducted further offshore and deeper; the government (Department of Fisheries and Oceans) estimates the footprint is now over 38,000 km2 along Canada’s Pacific coast.
The size of the thornyhead population in this area is unknown. Your annotations will increase our data on species diversity and distribution in known trawling areas and perhaps increase our understanding of deep-sea ecosystems in response to human disturbance.
For this mission, in addition to your annotations on the variety of sealife, we ask that you pay particular attention to the trawl marks and thornyhead rockfish. Trawl marks appears under “Objects” and thornyhead rockfish has been added to “Sealife”.
Click “more” for examples of the images you will see.
Below are a few more images like the ones you will see in the video clips: