A pied-billed grebe catches a bullfrog in its bill. I’ve seen a variety of predators at Ridgefield eating bullfrogs but the two I see the most are grebes and bitterns. I don’t know if this is a reflection of how often these two species eat bullfrogs or a reflection of how much time I spend watching these two species. Given that both are favorites of mine, I suspect more of the latter than the former.
Many animals have a nictitating membrane, a translucent third eyelid, that they can close to protect their eyes while still providing some visibility. When photographing birds on a windy day, I take more pictures then normal as they frequently close these eyelids to protect against the dust and debris being blown about.
Of course wind is just one reason they might do this, they also might close them if, for example, they are trying to swallow an enormous bullfrog and are worried about bits of frog scratching their eyes. On this great blue heron, you can see the membrane in mid-blink, sweeping backwards horizontally from the front of the eye. Bullfrogs themselves also have this membrane, here you can see it on the male coming up vertically from the bottom of the eye.
Bullfrogs aren’t native to the Northwest but a variety of our native species have adapted and added bullfrog to their diet, not that it has slowed the expansion of this invasive species. I once saw a pied-billed grebe eat a bullfrog whole, but most of the time they break the bullfrog into pieces by spinning it about and thrashing it in the water.
But let all who take refuge in you be glad; let them ever sing for joy.
The bullfrogs were singing in rare form at the refuge this weekend. Breeding season was in full swing and the males were croaking and wrestling and leapfrogging each other, and a few lucky ones were mating with the females. They were in a channel beside Bull Lake so I had to shoot down on them between the tall grass. Between a gentle breeze that constantly moved the grass about and my temporary bout of photographic incompetence, it took me a while to settle in and find my way.
This male was one of my favorites. I wanted to catch the ripples made by his croaking but was a bit surprised that my favorite view of the ripples is before his throat fully expands. The problem was that by the time his throat is fully extended, the ripples interfered with each other as they bounced off his rear legs, breaking up the pattern.
Beautiful creature, this one. Beautiful.
When a bittern strikes at prey unseen I never know what it’s going to come up with, but often I can guess based on the location of the strike. When this bittern lunged out into the water, I guessed it would bring up a bullfrog, but I wasn’t expecting a tadpole! And such a large one! Fortunately for me it repeated the performance a moment later when I was better positioned for pictures. Despite their size the tadpoles were still relatively early in their development as they hadn’t yet started to grow legs.