As a species, we humans have always been curious about what goes on deep in the ocean where we can’t see. But since the deep ocean and ocean floor remained inaccessible for a long time, we made up stories for what could be there instead. Well, we looked and I’ll share what we found with you but before that, let me ask: what do YOU think we’d find if we look on the ocean floor?
There are generally two lines of thought:
In this case (and to everyone’s surprise), we didn’t find either. Actually, how we were able to take a peak at what lies on the ocean floor was not through direct observation. Instead, we used a technique called dredging.
Dredging is a way of collecting material (sand, stones and living creatures) that lie on the ocean floor and bringing them up to the surface. In practice, this is done by sending down a small net and dragging the net on the ocean floor using a boat and then bringing the net back up.
Here’s a visual of what that looks like:
We were lucky enough to be able to do this at Barkley Sound where there are a vast diversity of creates dwelling on the ocean floor. What we found was that the ocean floor hosts a lively and flourishing community of animals!
There are crabs, sea cucumbers, many sorts of sea stars, clams and giant moon snails that all call the ocean floor their home!
When dredging, you also get a lot of broken shells and remains of other animals (usually their bicarbonate exoskeleton). Some of these shells can reveal how the animals that once lived in them met their deadly faith….
When you pick up a lot of empty shells, you might notice that despite their variety, some of them share a common property: they have a peculiarly round hole in their shell. Well, these holes are driven by snails that use their tough set of teeth-like structures (radulla) to drill into the shells and get their treat! Pretty cool, right?
So on the ocean floor lies the remains of animals past and the bodies of animals present and alive. It’s a thriving community of living creatures! Now, everytime we dredge a certain area, we essentially disrupt a part of this thriving community by sweeping everything from the ocean floor and bringing them up to the surface. As you can imagine, this can be quite damaging to the animals and the ocean floor habitat.
We must take extra caution to not dredge in overly sensitive habitats and make sure that we don’t dredge a large area repeatedly – or else we can risk damaging the area extensively and destroying the natural habitat of its organisms.
If you like to find out more about what lies on the ocean floor (and do so without damaging its sensitive habitat so much), BBC has an awesome series of videos that highlights the creatures that live on the sea floor.
You can check them out here: http://www.bbc.co.uk/nature/habitats/Benthic_zone
Photo edited by me.