BirdWalk Newsletter

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1 BirdWalk Newsletter Walks Conducted by Perry Nugent Newsletter Written by Jayne J. Matney Not Really Pitch Black Ravens, Crows, and Blackbirds Photo by Guenter Webber At this time of year, our present western culture is consumed with scary, creepy, and mysterious. Sometimes the blackbirds, ravens, and crows are used to pull this off. Black may suggest to some people thoughts of evil or death. Of course, it didn t help their non-benevolent cause when Edgar Allan Poe wrote The Raven. These birds get a bad rap and then at other times are hardly acknowledged or noticed. At first glance, black birds, such as crows, red-winged blackbirds, ravens, and grackle seem like uninteresting, drab birds. However, if you look at them

2 closely, and study them more thoroughly, they may surprise you. First of all, the black you see has an iridescence to it which shows many glossy colors reflecting off from the sunlight at different angles. Secondly, there are some interesting facts about them that most people would not know. Photo by Guenter Weber In ancient culture and Native American culture, the black birds represented good passage and protection or a benevolent message or happy tiding. Other writings indicate that black birds of any type represent a higher intelligence, higher understanding of the universe, secrets, and mysteries. Unable to gage whether they have a higher understanding, researchers have shown that the crow certainly is a good example of high intelligence. They have been known to be one of the few animals that can perceive and solve complex problems and use tools or the environment to gain a solution to those problems. Besides large and black, the most repeated descriptions used for the crows are intelligent, adaptive, sociable, and opportunistic. Ravens are mostly found in Western North America, but the raven and American Crow distributions overlap. I value my garden more for being full of blackbirds than of cherries, and very frankly give them fruit for their songs. Joseph Addison, The Spectator Looking at the more common black birds in this area, the list includes: American Crow, Fish Crow, Boat-tailed and Common Grackles, and of course, the Redwinged Blackbird.

3 American Crow (Corvus brachyrhynchos) Fish Crow (Corvus ossifragus) Not to be mixed up with the ravens, crows are smaller than ravens but larger than grackles and other blackbirds found here. When comparing crows to our other black birds, look for larger size, relatively long legs, thick neck, and a heavier bill. Their wings are broad and rounded, and when in-flight the wing tips may spread out like fingers. Unlike the raven tails, which have a long section in the center, the American Crow has a tail that is straight across on the end. They are completely black, even their legs and bill, while their feathers are black, glossy, and can show iridescence at its finest. Crows can be found almost anywhere and are widespread throughout the country. As long as they have a place to perch and a dependable food source they will stay around. They may be found in fields, river sides, and woodlands, as well as parking lots, roadsides, garbage dumps, etc. This shows that the crow will feed off of a wide variety of things. In addition to the normal bird food such as insects, frogs, snakes, seeds, grains, and berries, the crow will eat snakes, carrion, other birds eggs, turtle eggs, and garbage. Even though they can be scavengers, their bill cannot tear carcasses. Therefore, they must wait for another animal to begin feeding before they can take part. Being opportunistic, they are sometimes Thief carrying an egg considered thieves. Don t be surprised if Photo from Guenter Weber you see a crow taking dog food out of a bowl, or raid a picnic table that is not being watched. When in flight, it rarely glides. It has a consistent and slow method to flying. In courtship, the male puffs out by spreading its feathers, and bows to the female which he is trying to impress. Once paired up, the birds will make

4 physical contact with each other often by preening each other and touching beaks. They nest at least 10 feet above the ground with both in the pair contributing to the structure. Their nest is usually large and made of sticks, grasses, bark, and mud, then lined with moss and feathers. Eggs are dull bluegreen to gray-green with brown and gray blotches. Even though the tending of the eggs is solely the female s responsibility, the feeding is done by both parents once the babies are hatched. The pair may also get help from other crows in their social circle such as last year s babies! These crow flocks seem to be significant in their lifestyles. In winter, they tend to roost together by mingling into other family units producing an army of individuals. When communicating, the crow has more of a Caw-Caw sound while the Ravens have more of a croaking sound. Crow among the berries Photo by Guenter Weber According to an article with Audubon by Nicholas Lund, called How to Tell the Difference Between Crows, trying to tell the difference between crows in North American is a real pain and goes further to say, if you see a crow but it doesn t make any noise, you re not going to be able to make a positive ID. No

5 one can not with 100 percent certainty. Not even the pro birders. Not even me! American Crows are known for their caw-caw or caaaaaaaaaawwww vocalizations while the Fish Crow is more nasal with sharper caw caw caw without stretching out the awwww. Fish Crows are typically found around water habitats, but American Crows can also be found there. According to the North American Breeding Survey, American Crow have a much higher global breeding number with 27 million versus the Fish Crow with 450,000. Crows are extremely susceptible to West Nile virus which has been known to be one of the culprits for their downfall in past years. In the more present years, the American Crow population is considered stable, while the Fish Crow are slightly increasing in population. Crows are protected by the Migratory Bird Treaty Act. However, some states consider them a pest bird and allow some hunting of these species. Fun Facts About Crows: One nesting pair of Fish Crows adopted a young Blue Jay which appeared in their nest. The jay disappeared after 2 weeks of care. Communal roosts of crow can range from a few hundred to two million individuals! Some roosting sites have been functioning in the area for at least 100 years. American Crows are not at maturity to breed until they are at least two years old. The oldest known wild American Crow was over 16 years old when it was last captured and released. The oldest captive crow was in New York at 59 years old! Cornell Lab of Ornithology describes examples of crows problem solving and manipulation skills. One incident was described where a captive crow used a cup of water to pour into a bowl of dry mash. Another crow shaped a tool out of a piece of wood and used it to poke into a hole in a post looking for food, while another broke away pieces of pine cone down

6 onto tree climbers approaching a nest. They have also been known to take nuts and throw them on the roads where automobiles can crack them open for them. But there in your stony and windswept garden A blackbird is confirming the grip of the land. You, you, he murmurs, dark purple in his voice. Anne Stevenson North Sea Off Carnoustie Grackle with a nut or egg? Photo by Guenter Weber

7 Common Grackle (Quiscalus quisculla) Boat-tailed Grackle (Quiscalus major) Smaller than both the ravens and the crows, and having narrower beaks, grackles are another Grackle Photo by Marina Coppedge blackbird in our vicinity. Liking open or semi-open habitats, the grackles gravitate to open fields, grasslands, meadows, farmlands, groves, swamps, riversides, etc. The Boat-tailed Grackles are very distinctly linked to tidewaters, therefore are found along coastal areas in marshlands instead of being found inland. Adaptable to humans, they make use of parking lots, feed lots, parks, and cemeteries. When they roost in groups, they choose dense woods close to open areas. When these birds come in for breeding in our area, males are very obvious about their territories. The males will get up in the tree tops or high shrubbery and call out or sing with loud and sometimes obnoxious crooning. Also in their repertoire is an aggressive beating or fluttering of their wings. When they search for food, they will forage by walking on the ground, wading in shallow water, or perusing along branches in the trees and shrubs. They eat mostly seeds, grains, berries, fruits, insects, and small animals. According to the literature, scare-crows should be called scare-grackles as they are the leaders in eating farmers corn and grains. Common Grackle usually stick to more dry foraging while the Boat-tailed Grackle has no problem getting down in the water or mudflats. Grackles will also dip dry foods into a water source before eating. With their strong beaks, they can pry open mussel shells and break snail shells for food. When they roost, grackles will not hesitate to mix in with other types of blackbirds. When distinguishing the two types of grackles found in the area: The Common Grackle is smaller in length than the Boat-tailed Grackle but stockier with a shorter more slender bill. The Boat-tailed Grackle emits a more purple iridescent sheen,

8 while the Common Grackle has more of an olive sheen on the body and purple on the head and chest. The females of both are more muted in colorationusually more of a brown or rusty nature. The young are brownish with dark eyes. The Boat-tailed Grackle has an extra-long wedge-shaped tail, while the Common Grackle has a shorter, V-shaped tail. Both grackles found here on the east coast have yellow to golden eyes. Mating behaviors for grackles can range from wing fluttering, calling, a group of males flying with a slow moving female, or a female with a single male flying together either with great speed in a chase or flying slowly together side-by-side. Both grackle types nest in colonies. The eggs vary somewhat. The Common Grackle s eggs are pale blue blotched with brown, while the Boat-tailed Grackles eggs are more pale greenish blue with brown, gray, and black markings. The Boat-tailed Grackle female does the care giving to the young, while the Common Grackle pair shares the feeding responsibilities. Both types of grackles have seen dramatic declines between 1966 and Vocalization Photo by Guenter Weber The Common Grackle has had a 58% cumulative decline, while the Boat-tailed Grackle has had a 47% cumulative decline during this time period. The good news is that the North American Breeding Bird Survey estimates a 61 million Common Grackle breeding population, and a 2 million Boat-Tailed Grackle breeding population. Remember these two numbers are so different from each

9 other because the Boat-tailed Grackle is much more limited in range due to its connection to the marsh areas. Iridescence at its finest- Grackle Photo by Jo Frkovich Fun Facts About Grackles: Fledgling Boat-tailed Grackles that accidently fall into the water can swim well for short distances by using their wings like paddles. As long as there are no alligator or other predators around, they can make their way to the banks. Boat-tailed Grackles have a harem defense polygyny system in which the females nest in colony format and only one male is selected to mate and defend within that area. However, when the females leave the colony space, she may mate with other males outside of the chosen defender. Grackles have a scoring blade on the inside of their top beak which can cut open acorns and other harder foods.

10 Anting is commonly seen in grackles. This behavior involves the grackle sitting or hunching down on the ground with wings open and letting ants crawl up their bodies. The scientific explanation for this bizarre behavior is that the formic acid which the ants secrete in their sting rids the bird of parasites that may be dwelling within the feathers and on the skin surface of the birds. According to the Cornell Lab of Ornithology, other products having been seen to aid in riding the bird of pests is walnut juice, lemon and lime juices, marigold blossoms, chokecherries, and mothballs. The oldest recorded Common Grackle was a 23 year old male eventually killed by a raptor in Minnesota. Red-winged Blackbird (Agelaius phoeniceus) A Swedish scientist, Carolus Linneaus, started binomial nomenclature of a two word naming system to living things. With the use of Latin and Greek, we now use this system even today. The Redwinged Blackbird s scientific Red-winged Blackbird Photo by Marina Coppedge name was given to them by Linneaus himself, and it comes from Greeks words for flocking and red. Redwinged Blackbirds are what we in the south call snowbirds. They may travel as far as 800 miles south for their winter migration. However, here we have our own permanent residences, too. In the north, they are primary indicators for spring. The Red-winged Blackbirds are smaller than the grackles, crows, and ravens. They are considered a stocky blackbird with slender, conical bills and medium length tails. When perched or sitting, their tails flare slightly and they look a bit hunched. The most noticeable characteristics is their sleek, black body feathers and a shoulder patch of red/orange and yellow of the male s plumage which he

11 brilliantly displays when being bold. Females are simply dark brown with streaks, lighter on the breast, and fashion a whitish eyebrow. Their diet consists primarily of insects and seeds. During winter, they will congregate in large flocks with other types of blackbirds including starlings. During breeding season, we see them congregating amongst our impoundments housing fields of cattails. During breeding season, they prefer freshwater impoundments and salt water marshes where the vegetation is usually dense with bladed grasses. Otherwise, they will harbor themselves in open fields, woodlands, and grasslands. The males are notorious for perching on the highest of the cattail blades and calling out while puffing their feathers. They do this for two reasons: 1. Territorializing 2. Attracting mates. Being highly polygynous, the male will establish himself with an area and mate within that area with many females. However, the female may leave that area during the day and mate with other males. These territorial males are very fierce about defending their territory from other males and from predators. Therefore, it is advantageous for the females to nest within the defender s realm. The females build the nests using wet grasses, bark, wood pieces, leaves, and mud. They typically choose to build the nest between the long, upright stalks of a marsh or blades in a cattail field. Therefore, while the males are busy showing off and making themselves very conspicuous at the tops of the blades, the females are sneaking and gliding through the grasses as they collect food and building materials. The nest will house 3 to 4 pale bluegreen eggs with black, brown, and purple markings. Once they hatch, both parents engage in feeding the young. According to the North American Breeding Bird Survey, the Red-winged Blackbird population has declined 30% Shoulder Patch on Display between 1966 and 2014, and has gone Photo by Guenter Weber from 190 million to 130 million since However, they are still considered one of the most abundant native birds on the continent.

12 Fun Facts About Red-winged Blackbirds: Red-winged Blackbirds have been seen using their slender bills to probe and break open the bases of aquatic plants to capture insects there. Ragweed is a common allergy problem for many humans. Redwinged Blackbirds eat seeds from weed-like plants such as ragweed and cocklebur. Thank you! An investigative field experiment was done looking at subspecies of blackbirds that had distinct size and proportion differences. When they switched the babies in the nests, the babies grew up as their respective foster parents size and proportion. Therefore, the size and proportion differences were not genetically based, but rather environmentally based. The oldest recorded Red-winged Blackbird was almost 16 years old when it was found injured and released back out after recovery. In California there is a subspecies of Red-winged Blackbirds which do not sport the yellow portion of the shoulder patch. Therefore it is nicknamed the bicolored blackbird Winter time flocking of these blackbirds can form congregations of several million birds! In the mornings, they spread out to up to 50 miles for foraging, then they return to flock together in the evening. Flocking Begins Photo by Guenter Weber Information for this article compiled from: Cornell Lab of Ornithology, American Crow, Fish Crow Redwinged Blackbird, Common Grackle, Boat-tailed Grackle ; Kaufman, Kenn, Lives of North American Birds, Audubon Field Guide; 7 Surprising Facts About Red-winged Blackbirds, Birds and Blooms; Grackles- Are You Getting them Right? Ebird.org; Birds as Omens and Signs, exemplore.com; What Does A Flock of Blackbirds Symbolize, Quora.

13 Green-winged Teal Photo by Perry Nugent On October 29th, 2017, a breezy cool day at the plantation, two participants walked around the property with Ray Swagerty to find 40 species of birds. First bird seen in the parking lot was a Black-andwhite Warbler. Another was seen later on the walk in the woods near Ravenswood. Ravenswood Pond area was a treasure trough for sighting birds. Highlights of the Ravenswood area: Gadwall numbering at 12 which is a nice number for early season, our first sightings of Green-winged Teal for the winter was one pair swimming around on the pond s surface 20 feet away from the other duck groupings, and a Marsh Wren seen on the dry side at the right of the dike. Also seen at Ravenswood were the Wood Duck, Blue-winged Teal, Pied-billed Grebe, Great Blue Heron, Great Egret, Little Blue Heron (immature), and the Tufted Titmouse. Perched in a tree in the Ravenswood pond was a White Ibis. Seen at Ravenswood and in the Audubon Swamp were Common Moorhen. Some of these moorhen look to be

14 immature; perhaps they are of a later brood. In the Audubon Swamp, Yellow-bellied Sapsucker, Yellow-rumped Warbler (or Butter-Butts ), and Red-winged Blackbird were counted. Also in the Audubon Swamp on the boardwalk at the cemetery was a single Blue-gray Gnatcatcher. Viewed from the Audubon Swamp boardwalk past the cemetery and toward the more hidden section of the swamp, two Cedar Waxwings were seen. This was particularly special in that they are early in for the winter. Near the cabin area, Common Yellow-throat and Yellowbellied Sapsucker were located. Red-shouldered Hawk showed themselves near the cabin woods and near Ravenswood. Northern Flicker, Eastern Bluebird, and the Gray Catbird were seen near Fernanda s Field. Scattered throughout the property were: Redbellied Woodpecker, Downy Woodpecker, Pileated Woodpecker, Eastern Phoebe, Carolina Chickadee, Carolina Wren, and Northern Cardinal. Additional Species seen were the Blue Jay, American Crow, Fish Crow, Northern Mockingbird, Turkey Vulture, and Black Vulture. A grouping of gull flew by, but due to the grey overcasting and the distance, species were not identified. At the end of the walk, while the field sheets were being tallied, and refreshments were being served, Tree Swallow and a Belted Kingfisher were sighted. The Chimney Swifts and the Hummingbirds are noted as being gone from the area for the season. Yellow-rumped Warbler Butter Butt Photo by Marina Coppedge