Subject:
On a Mauritian mudflat between mangroves at low tide, different species of fiddler crabs (family Ocypodidae) pick up chunks of sediment and filter out anything edible.
There are several species of these semi-terrestrial crabs in this wetland exposed by low tide. We were able to identify the Tetragonal Fiddler Crab (Gelasimus tetragonon) and the smaller East African Fiddler Crab (Cranuca occidentalis).
The biggest problem for filmmakers or videographers with these animals is that they are very shy and wary. At the slightest detection of movement, these crabs rush into their burrows, only to reemerge minutes later. To film these small semi-terrestrial crabs, the person behind the camera must lie as still as possible and try to blend in with their surroundings—a difficult task on a mudflat for an adult person more than 1,000 times larger than this crustacean. One way to bypass these problems and showcase these incredibly interesting creatures is with time-lapse videography.
Technique:
This scene was filmed with a GoPro camera in a stationary position over several minutes. Instead of filming at a normal frame rate of usually 24, 25, or 30 frames per second, only 1 frame per second was used. So, 24 seconds of real-time made only a single second of recording, resulting in a time-lapse. Time-lapses are used to showcase changes and movements over a longer time and can visualise what would be nearly impossible to see in a real-time recording.
To make a time-lapse stand out, it is best filmed, at least in this case, on a day with clouds present. By casting moving shadows on the muddy mangrove marsh and the huge basaltic monolith in the background, with a summit of 556 meters (1,824 ft) named “Le Morne Brabant,” the clouds add an extra dimension to the recording besides the movement of the crabs.
Little action cameras have a habit of distorting the image they record considerably. Underwater, this distortion is usually most noticeable at the edges. It results from inappropriate camera settings combined with movement. When filming landscapes, the distortion often results in a convex horizon. The natural bending of our horizon is impossible to witness when standing at sea level. To straighten this horizon in film footage, special dedicated software needs to be applied in post-production. Most editing software programs have this feature built-in, and with a few clicks, you can easily straighten your horizon.
Because it’s difficult to change the settings while filming a time-lapse, it is necessary to color correct your footage before broadcasting. As you might have noticed, the light intensity changes constantly in this video clip. Clouds come and go, and so do their shadows. To enhance this footage, the contrast has been increased. By making the dark areas slightly darker and the lighter areas slightly lighter, the footage became a bit crisper. Also, the blue of the sky was intensified.
Time-lapse video has no sound, but to give an extra dimension, we added, besides music, the noise generated by little crabs walking over wet sand.
Filming location:
This short underwater videoclip has been filmed in Mauritius 🇲🇺
Watch it on YouTube:
You can watch it directly on YouTube by clicking the following link: https://www.youtube.com/watch?v=wZOcKHqNOac
More about this subject:
For more in-depth description about other fiddler crab species:
The East African Fiddler Crab (Cranuca occidentalis) vlog post 172 or click the following link
Tetragonal Fiddler Crab (Gelasimus tetragonon) vlog post 160 or click the following link
https://www.beyondscuba.com/post/tetragonal-fiddler-crab-gelasimus-tetragonon
and
Perplexing Fiddler Crab (Uca perplexa) vlog post 39 or click the following link
Join us on a journey of discovery and entertainment as we explore fascinating marine wildlife topics and explore the many exciting underwater adventures on our YouTube channel and our Facebook page!
Also you can capture the magic of the underwater world with our online Marine Wildlife Videography course!