Archivos de Diario para marzo 2018

viernes, 09 de marzo de 2018

Ecological Physiology

Julia Pupko
Field Observation 2: Ecological Physiology
3:30 to 6 on Tuesday, February 20th, 2018

Today was overcast and 43 degrees. We drove out to Dead Creek Wildlife Management Area in Addison County. On the drive to Dead Creek, we saw six Red-tailed hawks, two Common Ravens, and a Mourning Dove. After arriving at Dead Creek, I took a moment to make note of the landscape. Most of the region is agriculture fields, interspersed with fragmented deciduous forests, ponds, streams, and wetland areas. The vegetated areas give the birds we saw a place to roost, and the agricultural fields provide a good foraging spot. A lot of snow had melted and the fields we were navigating were completely mud soup. We were on the prowl for an owl, a snowy owl to be exact.

The first bird we saw at Dead Creek was another Red-tailed Hawk. She was massive, and kindly perched in a tree next to the road for us to admire her. After she flew away, we continued on, seeing a pair of Mallards. Then we saw her: our first Snowy. She was contently perched on a fence post next to a pond. As I gazed at her through the scope, she turned her head and calmly met my gaze. I was ecstatic… Snowy Owls were a life bird for me. We slogged over to another field and saw the second Snowy of the day.

Snowy Owls have interesting winter migration pattern. It is sporadic, but numbers of them move south during the winter, which is why we were able to peep these beauts. The erratic nature of their migration seems related to food abundance: when there are high populations of food during the breeding season, a higher number of Snowy Owl eggs will be laid and hatch, so more migrate south during the winter. This is different from many species who migrate when they are starving. To save energy, Snowy Owls have adapted to sitting still in open places when they hunt, waiting until they see prey. They hunt a variety of prey, usually rodents such as lemmings, but will occasionally take down bigger prey like geese. Lemmings are the staple of Snowy Owls when they are in the northern portions of their range. I am so grateful I was able to share the space with these magnificent visitors.

Publicado el viernes, 09 de marzo de 2018 a las 03:48 AM por jpupko jpupko | 5 observaciones | 0 comentarios | Deja un comentario

domingo, 25 de marzo de 2018

Social Behavior and Phenology

Julia Pupko
Observation 3: Social Behavior and Phenology
Friday, March 23rd from 2:45pm to 7:15pm

Today was a partially cloudy day with temperatures hovering around 40 degrees F. Once again, we headed out towards Dead Creek Wildlife Management, stopping there before continuing to the Champlain Bridge and hitting Lake Road in Chittenden County on the way back. The habitats spanned included open agricultural fields, wetland regions, open water, riparian zones, and open fields. Some of the most common tree species included American elm, eastern cottonwood, and silver maple. Most of the agriculture fields were corn fields and the open meadow appeared to be vegetated with native grasses.

On the way to Dead Creek, we saw our first few species: a Northern Harrier and a Turkey Vulture. Immediately upon arrival at Dead Creek, we saw around 10 Horned Lark, a Red-tailed Hawk, and a large flock of Mallards and Canada Geese. After watching them for a while, we continued on to the Champlain Bridge, where we saw roughly 100 Canada Geese, 5 Mallard, 16 Ring-necked Duck, 40 Greater and Lesser Scaup, 12 Common Goldeneye, 4 Common Merganser, 7 gull spp., a Bald Eagle, and a lone Snow Goose. The lone Snow Goose may have been a Ross’s Goose, as we later saw a large flock of Snow Geese at Dead Creek and would not expect this goose to have left the flock, but the bill appeared to be a little too long to be a Ross’s Goose, so we did not make a positive identification.

Watching the water birds interact was a treat. We observed many flocks of Canada Geese coming and going, flying in their v-formations as they flapped towards their destination. The group dynamic was awesome, with everyone honking and communicating with each other. The geese communicated with a combination of honks and hisses, letting each other know when one individual was invading another’s personal space and when close contact was acceptable. Many of the flocks of ducks freely mingled with the geese, happily dabbling and diving. Many duck species like Mallards will touch down in the same place as geese while migrating, possibly looking to the geese to find good feeding spots and for the protection offered by the larger species. The male Common Goldeneye were particularly fun to watch, as they have begun their mating displays, flaunting themselves by fluffing up and flipping their heads back. Their actions appeared to be primarily mating displays and not territorial displays, as the group is still migrating together and acting as a social unit. When waterfowl are not migrating, they are generally much less social and much more territorial, but during migration, it is advantageous to remain associated with a group for protection and the flight assistance that comes with travelling long distances in a v-formation.

We left the bridge and headed back towards Dead Creek. Once back at Dead Creek, we saw a flock of several hundred Snow Geese and Canada Geese, another Red-tailed Hawk, and 3 American Crow. After bopping around in the area for a while, we started trekking towards Lake Road near Charlotte Town Beach to look for Short-eared Owls that had been sited there. On the drive, we saw a Snowy Owl (we stopped and admired him for some time), a Rough-legged Hawk, a small flock of European Starling, a Red-winged Blackbird, and a Northern Harrier. Once we got to Lake Road, we were gifted with two Short-eared Owls, a Red-bellied Woodpecker, and another Northern Harrier.

Watching the Short-eared Owls was a treat. They emerged at dusk, as they are particularly active in the evening. Short-eared owls hunt in open fields, soaring over the field looking for rodents. Every once in a while, they would stop soaring and hover, before spiraling and dropping onto the ground to snag a rodent. One of the owls caught something and appeared to stash it to continue hunting. After several minutes of flying, the owls would perch on a fence post or bush for several minutes and survey the field before continuing on.

As I watched the Short-eared Owls soundless flight, I compared their plumage to that of Mallard Ducks. Mallards have very water-proof feathers and brown plumage with black-edged feathers. The coloration of their plumage is cryptic, making it more difficult for predators to see them, especially while nesting. Their flight is very noisy, as they have no need for silent flight. The Short-eared Owls, in contrast, have silent flight, which helps them with hunting. Their plumage is dark brown and black mottled on the back and lighter white with light stripes on the stomach. A light underside makes them blend in with the sky when looking up, which makes it easier for them to sneak up on prey without alerting prey to their presence. A darker topside helps them blend in more with the ground when looking down on them from above.

Publicado el domingo, 25 de marzo de 2018 a las 11:52 PM por jpupko jpupko | 20 observaciones | 0 comentarios | Deja un comentario