Neotropical birds are fairly well acquainted with repetitive periods of thundershowers. With that in mind, we decided not to waste this stormy Tuesday by remaining indoors.
Periods of rain need not put a damper on a day outdoors observing birds that wintered in a rain forest or other tropical environment.We hiked this utility right-of-way to the north of a heavy thunderstorm and found plenty of activity in the shrubby successional habitat there.Rain or shine, male Indigo Buntings were busy singing. All this exuberance is intended not only to establish and defend a nesting territory……but to attract the attention of a mate as well.Prior to the implementation of the intensive manicuring practices we see currently applied to most utility right-of-ways, shrubby thickets filled miles of these linear corridors to create a webbed network of early successional growth throughout the lower Susquehanna valley. Loss of this specialized habitat has led to the almost total elimination of the formerly common Blue-winged Warbler as a breeding species here.We found three male Blue-winged Warblers singing on territories in this bushy clearing where electric transmission lines pass over Third/Stony Mountain on State Game Lands 211.Their presence at this site is testament to the importance of maintaining corridors of quality successional habitat in the landscape.The Blue-winged Warbler is a Neotropical migrant with an easy-to-learn song. It’s a very simple, buzzy sounding “beeee-bzzz”.Another Neotropical species that nests in successional thickets is the Prairie Warbler (Setophaga discolor), seen here during one of this morning’s downpours.The Prairie Warbler can sometimes be found in stands of pioneer plants like Eastern Red Cedar on sites with barren soils or those that have been subjected to wildfire.The Hooded Warbler is fond of wooded thickets along the edge of forested land such as those in the Third/Stony Mountain utility right-of-way.The presence of a Mountain Laurel thicket also enhances a forest’s ability to host breeding Hooded Warblers.
We hope you enjoyed our walk in the rain as much as we did. If you venture out on a similar excursion, please remember this. The majority of the wild animals around us have busy lives, particularly at this time of year. Most don’t take a day off just because it rains—that includes ticks.
Be certain to check yourself for ticks, especially these very small Deer Ticks (Ixodes scapularis), also known as Black-legged Ticks. Deer Ticks are vigilantly looking for something to latch onto, even in the rain, and they can be vectors of Lyme disease. We found this adult female as a stowaway on the editor’s neck just before heading home from today’s stroll.
Back on March 24th, we took a detailed look at the process involved in administering prescribed fire as a tool for managing grassland and early successional habitat. Today we’re going turn back the hands of time to give you a glimpse of how the treated site fared during the five months since the controlled burn. Let’s go back to Middle Creek Wildlife Management Area for a photo tour to see how things have come along…
Pennsylvania Game Commission crews administering prescribed fire on a grassland demonstration site back on March 16.By late May, native herbaceous perennial wildflowers including Joe-pye Weed had re-greened the site. One of the goals of the burn was to kill fire-sensitive woody plants, thus preventing the process of succession from reforesting the site.The scorched, lifeless remains of small trees and shrubs indicate that that goal was met.Because prescribed fire is administered in a mosaic pattern that permits some early successional growth to remain until the next burn, birds including this thicket-nesting Yellow-breasted Chat are able to take advantage of the mixed habitat during their breeding season in May and June.By August, the site is a haven for native plants and animals.The burn has promoted the growth and late-summer bloom of fire-tolerant native wildflowers and warm-season grasses……including Indiangrass,……Big Bluestem……Thin-leaved Coneflower (Rudbeckia triloba), a plant also known as Brown-eyed Susan,……and Joe-pye Weed, a plant butterflies find irresistible.Eastern Tiger Swallowtail collecting nectar from Joe-pye Weed.A black-morph Eastern Tiger Swallowtail collecting nectar from Spotted Knapweed (Centaurea steobe micranthos), a non-native invasive plant found growing in an area of the burn site missed by this year’s fire. While many non-native plants are unable to survive the flames and heat produced by prescribed fire, it isn’t an absolute cure-all. It doesn’t eliminate all invasive plants, it just keeps them from dominating a landscape by out-competing native species. Left unmanaged, Spotted Knapweed is a tough perennial invasive that can easily become one the species able to overtake a vulnerable grassland. It can be a stubborn survivor of some prescribed burns. On the plus side, butterflies really like it.By August, native grassland plants in the prescribed fire area were already providing an abundance of seeds for birds including this American Goldfinch.For larger birds like turkeys and pheasants, an abundance of Carolina Grasshoppers are providing a protein-dense food source in managed grasslands.And tiny flying insects, a nuisance to us as we take a stroll alongside the grasslands, are a meal taken on the wing by dragonflies including this Black Saddlebags.
Elsewhere around the refuge at Middle Creek, prescribed fire and other management techniques are providing high-quality grassland habitat for numerous species of nesting birds…
Bobolinks nested both in areas subjected to controlled burns……and in hay fields where mowing was delayed until the nesting season, including the fledging process, was completed earlier this month.As advertised, Grasshopper Sparrows nested in these fields as well.
We hope you enjoyed this short photo tour of grassland management practices. Now, we’d like to leave you with one last set of pictures—a set you may find as interesting as we found them. Each is of a different Eastern Cottontail, a species we found to be particularly common on prescribed fire sites when we took these images in late May. The first two are of the individuals we happened to be able to photograph in areas subjected to fire two months earlier in March. The latter two are of cottontails we happened to photograph elsewhere on the refuge in areas not in proximity to ground treated with a prescribed burn or exposed to accidental fire in recent years.
Eastern Cottontail at a site subjected to prescribed fire earlier in the spring.Eastern Cottontail at a site subjected to prescribed fire earlier in the spring.
These first two rabbits are living the good life in a warm-season grass wonderland.
Eastern Cottontail at a site not subjected to any recent fire activity.Eastern Cottontail at a site not subjected to any recent fire activity.
Oh Deer! Oh Deer! These last two rabbits have no clock to track the time; they have only ticks. Better not go for a stroll with them Alice—that’s no wonderland! I know, I know, it’s time to go. See ya later.
It’s so tiny, you can’t even feel it crawling on your skin. It’s the Deer Tick (Ixodes scapularis), also known as the Black-legged Tick, and it’s already looking for someone to latch on to. Don’t let it be you. After your foray outdoors, be certain to shower and conduct a full body search for these little hitchhikers. Then, remember to launder the clothing you were wearing. Deer Ticks in the Lower Susquehanna River Watershed frequently transmit Borrelia burgdorferi, the bacteria that causes Lyme disease, and can be vectors of other microbiological pathogens as well. The specimen in this photograph is an adult male. Adult females are similar, but the edge of the abdomen has a crescent-shaped reddish border. The nymphal stage tick, which is half the size of an adult, is even more likely to infect humans with the Lyme disease bacteria, so be extra vigilant.
The Magi have arrived. Emanating from the shadows of a nearby forest, you may hear the endless drone of what sounds like an extraterrestrial craft. Then you get your first look at those beady red eyes set against a full suit of black armor—out of this world. The Magicicada are here at last.
This exuvia, the leftover from a cicada’s final molt, tells us they are here.A Brood X Periodical Cicada soon after emergence and final molt.Not to worry, cicadas are harmless and docile when handled. This is Magicicada septendecim, the largest and most common of our three species of Brood X seventeen-year cicadas. They are currently emerging along south-facing borders of forests and wooded parks and lawns.Magicicada septendecim can be recognized by the orange on the thorax behind each eye and in front of the wing insertions. The smaller M. cassinii and M. septendecula have no orange coloration between the eye and wing.Magicicada septendecim (seen here) has broad orange stripes on the abdomen. M. cassinii has an all black abdomen and M. septendecula, the rarest species, has narrow well-defined orange stripes.
If you go out and about to observe Periodical Cicadas, keep an eye open for these species too…
Spotted Lanternflies, one of our most dreaded invasive species, have hatched. These tiny nymphs about 5 millimetres in length were found feeding on a Virginia Creeper (Parthenocissus quinquefolia), a native vine in the grape family (Vitaceae).Deer Ticks, also known as Black-legged Ticks, are hanging around on vegetation of all kinds looking to hitch a ride on a suitable host. Don’t let it be you. This adult female, less than 5 millimetres in length, was washed loose during an after-hike shower.
If you visit the shores of the Susquehanna River during the warmer months of the year, there’s a pretty good probability that you’ll be taking a visitor along home with you. Not to worry, it won’t raid the icebox or change the television channels when you leave the room to get a snack. It won’t put you in the doghouse with the landlord for having a forbidden pet. As a matter of fact, you may not even notice your new companion. Sure enough though, it’s there, crawling through the luxurious warm fabric of your clothing and seeking out a good place to dig in and chow down. O.K., so now you’re worried.
Ticks, particularly the American Dog Tick (Dermacentor variabilis), are widespread in the Lower Susquehanna River Watershed. Like spiders, they are arachnids. They have a four-stage life cycle (egg-larva-nymph-adult) which, in the case of D. variabilis, requires a minimum of two months to complete. Females lay up to 6,500 eggs on the ground. Then the fun begins as the larvae with any hope of survival must attach to a small mammal to feed. They can survive for almost a year before finding a host. After a successful hookup and subsequent blood feast of up to two weeks duration, the larva drops to the ground, molts into a nymph, and finds another small mammal, usually a bit bigger this time, to feed upon. A nymph can survive for up to six months before needing to feed. Finding the second host, the nymph feeds for 3 to 10 days, then drops to the ground to molt into an adult. Adult American Dog Ticks can endure up to two years without feeding on a host. The adults mate and feed on larger mammals such as deer and domestic animals including, of course, dogs. After a blood meal of five days to two weeks duration, the adult female tick drops to the ground to lay eggs and initiate a new generation.
The adult American Dog Tick attaches to a potential host by hanging from vegetation and grabbing the passing victim with its forward legs to hitch a ride. If undetected, a female will find a nice warm spot and “dig in” to begin feeding. This male is looking for love, and in all the wrong places.
The American Dog Tick is renowned as a carrier of the Rocky Mountain Spotted Fever bacteria (Rickettsia rickettsii). The bacteria is vectored by the ticks from rodents to dogs and humans. The adult tick must be attached to the victim for a minimum of six to eight hours to transmit the pathogen. A rash spreading from the wrists and the ankles to other portions of the body begins two to fourteen days after infection.
Tularemia, caused by the bacteria Francisella tularensis, can be passed by the American Dog Tick.Symptoms can appear in three to twenty-one days and include chills, fever, and inflammation of the lymph nodes.
American Dog Ticks which attach to dogs, particularly near the neck, and are left in place to feed and engorge themselves for longer than five days can cause Canine Tick Paralysis. Symptoms usually begin to subside only after a recovery period following removal of the arachnid.
The American Dog Tick is exposed to Borrelia burgdorferi, the bacteria responsible for Lyme Disease, however, transmittal of this pathogen is by the smaller Deer Tick (Ixodes scapularis), also known as the Black-legged Tick. The Deer Tick is not presently common at Conewago Falls. In the adjacent uplands, it is widespread and is carrying Lyme Disease where the White-tailed Deity (Odocoileus virginianus), the preferred host for the ticks, is found along with mice and other small rodents, the source of B. burgdorferi bacteria. The Deer Tick easily escapes notice and cases of Lyme Disease are frequent, so vigilance is necessary.
SOURCES
Chan, Wai-Han, and Kaufman, Phillip. 2008. American Dog Tick. University of Florida Featured Creatures website entnemdept.ufl.edu/creatures/urban/medical/american_dog_tick.htm as accessed July 30, 2017.