Birthing time for Muskrats is late April/early May, so this year’s young are roughly a month old. Weaning begins now and young Muskrats, who have been able to swim since they were two weeks old, begin foraging for themselves. Parents continue to supplement their offspring’s diet during this transition. Although Muskrats are omnivores, the majority of their diet consists of the roots, stems, leaves and fruits of aquatic vegetation. However, when you’re feeding half a dozen offspring, you harvest whatever is available, including bedstraw (see photo).
Besides being known for their vocal repertoire, Northern Mockingbirds are famous for pugnacious defense of their territory, nest, and young. Even more than most songbirds, Northern Mockingbirds aggressively stand guard over their nestlings as well as their young fledglings. Potential predators risk being mobbed and chased by nesting mockingbirds. While the female incubates, the male spends most of his time perched high on trees or rooftops, acting as a sentinel, and will chase away any animal (including humans) that approaches the nest. Northern Mockingbirds have also been known to join forces with other birds, including cardinals, thrashers and doves, to chase away potential nest predators.
In 1935 Walter Rogers wrote a book on tree flowers (Tree Flowers of Forest, Park and Street) in which he described White Ash (Fraxinus americana) in the following words. “The Ashes are important trees with interesting features of form and foliage, but their flowers are among the least interesting.” I am of a different opinion, at least regarding White Ash’s male, or staminate, flowers.
White Ash is dioecius – individual trees have all male or all female flowers. Just before and as the tree is leafing out, the flower buds, located on the shoots of the previous season, begin to open. Male flowers are more noticeable than female flowers, partly because of the size of their clusters — there are between 200 and 300 flowers in each cluster – and their vibrant color (which resembles the fall color of some White Ash leaves). Being wind-pollinated, White Ash’s flowers lack petals as they would impede pollination. The stamens are a purplish-red, raspberry-like color until they mature, at which time the pollen’s yellow color is predominant. The flowers are soon hidden by emerging leaves, so now is the time to see if you agree with Mr. Rogers!
Unlike most young birds, Barred Owls fledge before they can fly. On average, they leave their nest when they are around eight weeks old, and don’t master flight until they’re about 12 weeks old. Fledging for a Barred Owl consists of climbing up out of the tree cavity where they spent their first two months, onto a nearby limb where its parents will tend to it. More often than not there is a nearby branch which it can hop to.
In the fledging depicted, the closest limb was a good 10-15 feet above the nesting cavity. With the help of its strong talons, beak and wings, the fledgling managed to scale the tree trunk up to a somewhat horizontal stub where it could get a good purchase. It may not have been the most graceful ascension, but the fact that it could manage to climb straight up for this distance without the assistance of any grasping fingers was impressive, to say the least. Fledged Barred Owls continue to be fed by their parents until they can fly and capture their own prey. (Photo: Barred Owl chick fledging – clockwise, starting from upper left)
Although male Baltimore Orioles have been known to partake in nest building, usually it’s the female who selects the specific site within the male’s territory and builds the nest. Located at the tip of a slender branch, this pendulous nest provides its occupants with as much protection from predators as is possible.
The material with which the nest is started usually consists of flexible plant, animal or human-made fibers, and provides support. “Springy” fibers are then woven into the inner bowl and downy fibers are used to line the nest. The oriole usually brings only a single fiber at each visit, and works it into the nest with a complex series of bill-weaving techniques. The nest is completed in roughly one week.
Construction material includes hair (especially horsehair), twine or string, wool, synthetic fibers (one oriole nest was made entirely of cellophane), various types of plant fibers including grasses, milkweed stems and grapevine bark, cottonwood or willow seed “cotton,” milkweed seed plumes and feathers. Females have been observed flying more than a quarter of a mile in search of construction material. (Photo: Female Baltimore Oriole on her first day of nest-building)
YESTERDAY’S MYSTERY PHOTO: Once again, Naturally Curious readers outdid themselves with creative solutions to a Mystery Photo. If you want a thoroughly enjoyable 5 minutes of entertainment, read yesterday’s comments! I will let you know if this mystery is ever solved.
Adult Painted Turtles leave their ponds in May, June and July to find a sandy spot in which to dig a hole and deposit their half dozen or so eggs. In most of their range, Painted Turtles hatch and emerge from their nest several months later, from August through early September. In the northern part of their range, however, the young turtles hatch in the fall but usually overwinter in their underground nest and emerge in the spring.
When turtles hatch, they use a modified scale called an egg-tooth, or carbuncle, located on the front of their upper jaw, to puncture their leathery egg shell. (Although referred to as an egg-tooth, it is not a real tooth.) Typically the egg tooth disappears in a matter of days or weeks after hatching. However, Painted Turtle hatchlings in northern New England retain their egg teeth through the winter, and emerge in the spring with it still intact, as this photograph demonstrates. (Thanks to Nancy and Rob Foote for photo op.)
I unintentionally neglected to mention the diameter of the holes in yesterday’s Mystery Photo. They were approximately 5” wide. Bank Swallow nest holes, similar looking and also dug into banks, are anywhere from 1 ½” to 3” in diameter. Being colonial nesters, Bank Swallows also typically have many more nests in a given bank (see photo inset) than Belted Kingfishers, which usually have one but may have several in a single bank, only one of which they occurpy during a given season.
After courtship takes place, a pair of Belted Kingfishers flies to a sand bank in a road cut, landfill or sand/gravel pit that is usually near water, and proceed to excavate their nesting tunnel. The male begins to slash and probe the soil with his bill while the female remains perched nearby, calling the distinctive rattling call of Belted Kingfishers. She eventually lends a hand (bill) and they call to each other throughout the construction of their nest.
The tunnel extends three to six feet into the bank, ending with an unlined chamber. (A bed of undigested fish bones, scales and arthropod exoskeletons from regurgitated pellets eventually forms.) Typically the tunnel slopes upward from the entrance, which may help drain any water that accumulates in the nest. Furrows directly below the bottom of the nest hole are made by the feet of the birds as they enter and leave the nest.
Belted Kingfishers are starting to lay their six to seven eggs which will begin hatching in three to four weeks. (Photo: female Belted Kingfisher)