May 17th, 2010 by Marc AuMarc

When hiking, it is very important to keep an eye out for bird pellets or animal droppings so you can collect them and analyze their contents. I typically carry some ziplock bags for storage, leaving some air in them to protect the contents while in my backpack. Below are some photos of what I believe are bird pellets that I collected on a recent walk. Bird pellets are made of indigestible matter (in this case primarily bones and fur) that are regurgitated by birds. I often see them beneath large trees where birds may roost, but in this case they were on a stone wall.

As you can see, this bird was primarily eating rodents. The bulk of the pellets was made of fur, but portions of the stronger bones, like the jaws and teeth, were still intact within the pellets. I did also find bits of beetle carapace, perhaps an hors d’oeuvr, as well. It may be interesting to note that there are no native rodents on the island, although mice and rats have been here for hundreds of years now. Of course, any migratory bird may also be used to eating rodents back on the continent where they are native.

March 17th, 2010 by Marc AuMarc

A couple months ago, I put some pretty serious scratches in my Ikelite dome, which clearly showed up in any wide-angle or fisheye photos I took with the dome. Rather than get a new dome, I got a Micro Mesh kit for acrylic restoration. It was about $40, or about a tenth the cost of a new dome.

Essentially it’s a bunch of very fine sandpaper that you use progressively. First, you use regular sandpaper to sand out the scratches, if they’re big enough to warrant that, and mine were. Next, you use the micro mesh sandpapers, which go from 1200 to 12000 grit. At each step, you sand in one direction, ninety degrees from the last step, making sure to eliminate any traces of the previous sanding. After finishing with all the sandpaper, you buff it with a special paste.

Does it work? Yes. As you can see from the photos, things start off looking bad, but quickly get better, until the dome is totally smooth again. The toughest part is the edge of the dome, where it is hard to always remove the previous sanding. In my case, I ended up with a few small sanding scratches at the edge of the dome, but they don’t show up underwater because water is essentially the same density as acrylic, so it fills in minor scratches.

December 13th, 2009 by Marc AuMarc

When I take the little camera out, it is often somewhat difficult to use the strobe, particularly in relatively shallow water where there is already quite a bit of light. In these situations, the strobe easily overwhelms the camera with light, even when set to low power. Yesterday I tried adjusting the exposure control darker, since the camera doesn’t have aperture or shutter speed controls. I think this did allow me to use a bit more strobe to capture colors without blowing out the pictures.

I also found a decapitated rat carcass floating in the bay.

December 11th, 2009 by Marc AuMarc

If you are walking shoeless on a rocky shore, you may find these tips useful:

  • If you find a usable sandal, wear it. Under most conditions, having one protected foot gives you a great deal more flexibility to find comfortable spots to step with your bare foot.
  • Also, if you are lucky, you may find another sandal.
  • If you find two sandals for the same foot, try wearing the larger one on the wrong foot.
  • Should you find a better sandal, trade up.
  • Be careful walking too far with just one found sandal. If it breaks, you may have to walk back with none.
  • When leaving the shoreline, stash sandals above the water line for future use.