Wednesday, April 28, 2021

Morning at the Pond

There are worse ways for a naturalist to spend a morning than to sit at the edge of a pond, camera in hand and the rising sun at your back.

And so, on a pleasant spring morning with camera pack on my back and a small folding chair I headed for a beaver pond to sit for an hour or so to see what there was to see. On the way to the pond I passed a willow shrub that was in bloom; and the spicebush was blooming in a patch of damp forest  –

Soon after I settled in on the edge of the pond amid a few small trees, a male wood duck flew in and landed on the pond’s far side –

He then disappeared into the cattails, never to be seen again.

Soon after a great blue heron flew in and landed in a dead tree about 100 feet away. There was time for a handful of photos before it left in the direction of a marsh a half mile away –

All was quiet for a while and then, in the far, far distance there was a black spot circling in the air. One of my camera’s powerful telephoto lens revealed it was an immature bald eagle. It’s not a good photograph because the bird was a long, long way away –

Soon afterward another fish-eating raptor appeared – this time it was right over the beaver pond and spent a few minutes overhead as it looked for fish beneath the surface. Not a bald eagle, this was a migrating osprey on its way north –

After a not finding a fish, the osprey moved on and there wasn’t any activity at the pond for quite some time. Eventually a pair of hooded mergansers that had been on a nearby pond flew in to land nearby –

And climbed up on water-soaked log

Also on a fallen log in the pond was a painted turtle basking in the sun

Like the heron and osprey, the mergansers left after a short time –

Meanwhile, the tree swallows that nest in woodpecker cavities in the pond’s snags had recently returned from South America and were exploring some of those dead trees –

The last bird of the morning was a red-tailed hawk soaring over the pond –

Heading home I passed the blooming willow, it was warm enough that honey bees were busy gathering pollen –

Time spent by a beaver pond is time well spent.

Wednesday, April 21, 2021

In the Spring ...

In the spring a young wood frog’s thoughts turn to … (do frogs have thoughts or only instincts?). In the spring wood frogs emerge from their winter quarters in the leaf litter on the forest floor where they often freeze solid, their cells kept from damage by glucose that fills each cell in the fall and acts as an anti-freeze. For a more complete explanation see this site

But now it’s spring and the wood frogs have emerged to head for their breeding pools. Wood frogs breed early in the spring, often before the pools are completely ice-free. Those pools can be roadside ditches, pools formed from snowmelt or after heavy rains or the classic vernal pool. Irrespective of how the pools are formed, wood frogs seldom successfully breed in water that contains fish, for fish readily devour the products of the frogs’ mating.

Male wood frogs normally arrive at the breeding pools before the females and begin calling. The frogs’ calls sound remarkably similar to the quacking of a duck –

When the females arrive and enter the pool they are grasped by the males (a position called amplexus). Other males are often grasped since an amorous male will latch on to any nearby frog. Fertilization is external as the females release hundreds of eggs and the males release sperm.

A single female is sometimes seized by several males, which occasionally results in the female’s death –

The fertilized eggs form a gelatinous mass, which often adheres to adjacent egg masses –

Depending on temperature, the embryos develop rapidly and in a few days their heads, bodies and tails are easily distinguished –

Shortly afterwards the eggs hatch and the tadpoles swim forth to feed on algae and other vegetation –

The tadpoles will die if the pool dries before they mature and transform into frogs. Depending on temperature and the availability of food the tadpoles develop rapidly and in about 60 days metamorphose into small frogs –

The tiny froglets disperse into the surrounding woodland to feed on invertebrates until the fall when they take shelter below ground for the winter.

Wood frogs’ breeding season is short, lasting only a few days in early spring. The day after the video in this post was taken there was not a frog to be seen in the pool, the frogs had returned to the forest to spend the warm weather there. But there were many eggs in various stages of development in the pool. A few days later there were thousands of small tadpoles in the pool. Only a few of those tadpoles will live long enough to transform into frogs and fewer still will survive to return to breed next year.

Wednesday, April 14, 2021

A Week at the Beaver Pond

Today we return to the beaver pond where the encounter with the mink occurred; one of my camera traps has intermittently been on the pond's shore during the last four years. As spring progressed the remaining ice on the beaver pond almost completely melted and it was time to put a camera trap back on a shoreline tree.

A number of wood ducks flushed from the pond when I went to put the camera in place, which raised the expectation of getting videos of wood ducks as well as beaver and other wildlife.

The camera trap is aimed at a fallen log that extends from shore into the water. The log began as a tree that fell into the pond in June 2019 after the area received over five inches of rain in three days. After that much rain, the saturated soil couldn’t support the tree's weight and down it went; the descent was captured by my camera trap and shown in the video in this post

Now, two years later, I placed a camera trap to view the log and the wildlife that uses it. Here are the results from the camera’s first week at the beaver pond –

The videos of the wood ducks were a treat (at least to me) and it was quite gratifying to get several videos of a mink running the log. The plan is to leave the camera in place throughout the spring and summer to capture videos of the wildlife using the fallen log.

Wednesday, April 7, 2021

Der Waschbär

Der Waschbär is the German term for an invasive exotic reportedly brought to Germany in the 1920s and 30s to be raised in captivity for their fur. Subsequently some were released into the wild as quarry for hunters and during World War II allied bombs hit one of the fur farms allowing more animals to escape into the wild.

Now, almost 100 years after the first introductions, there are an estimated one million of the animals in Germany. There are fears that this invasive exotic will spread to occupy all suitable habitat in Europe – preying on the eggs and young of native birds and mammals, eating native reptiles and amphibians as well as crops and fruit.

Der Waschbär translates into English as “The Washing Bear” which should be a clue to its identity.

The situation is much the same in Japan where this invasive exotic is known as araiguma. There are accounts of 2,000 araiguma being imported to Japan each year in the late 1970s and 80s, as pets – although there are other reports of a number being brought to Japan as pets by G.I.s after World War II. As pets they’re cute when young but aggressive and nasty as adults – many were released when they were no longer cute. Thus most of Japan is now occupied by araiguma.

And the identity of this invasive exotic: the North American raccoon –

And why is it called the washing bear? Not because it actually washes its food, but because it looks as if it’s washing as it searches for food in water bodies where it finds frogs, crawfish and an occasional fish, alive or dead.

Raccoons aren’t gourmets, they’ll feast on anything remotely edible; like humans they’re omnivorous. Here are raccoons living up to their name of der Waschbär –

North America is suffering from the introduction of species from afar; but it’s a two-way street, other parts of the world are also suffering from species native to North America – Canada geese, gray squirrels, bullfrogs, American mink, fall webworm and many more – as humans gradually homogenize the world’s flora and fauna.