Morning Flight Wednesday September 1, 2010

In Cape May, the first day of September felt like July in terms of temperature, but the bird diversity sure felt like September with increased numbers of mid-season songbird migrants (birds such as Northern Parula and Black-throated Green Warbler). Additionally, today was much better than yesterday in terms of overall numbers, even though we're dealing with weather conditions that are much the same. This has been an unusually long period of favorable migratory conditions (clear skies and light winds with a westerly component), and I've been enjoying my mornings on the Higbee Dike immensely as a result! The warbler flight is still currently dominated by American Redstarts, with Northern Waterthrushes coming in a distant second place, but that will likely soon change as we near mid-September. Species highlights today included a close and lovely Yellow-throated Warbler flying overhead and the continuing juvenile Baird's Sandpiper. Another highlight today was the beginning of the fall hawkwatch at Cape May Point State Park. Check this blog for hawkwatch updates from counter Melissa Roach.

One neat aspect of watching morning flight is assessing the subtle characters that can be used to identify warblers and other songbirds in flight. Often, logical connections can be made between useful ID characters (like shape and structure) and the underlying biology of the birds. One example is wing length in warblers. Though there is considerable variation among species, there is a positive correlation between wing length and distance of migration. Additionally, the longer-winged warblers appear to have wingtips that appear more pointy when the wings are spread. Below, there are photos taken today at the Higbee Dike of individual Magnolia and Blackpoll Warblers with their wings outstretched. Compare their wing shape and apparent length with their migratory habits in mind. Magnolia Warblers are neotropical migrants, but they winter only as far south as southern Central American and the Caribbean, and appear to make much of their southbound migration overland. Blackpoll Warblers, on the other hand, are champion migrants that make very long overwater flights to northern South America, with many wintering in the Amazon basin. A Blackpoll that leaves Cape May in the evening might not stop flying until it reaches Venezuela! Those long, pointed wings sure seem to be a great asset for long journeys through the skies.

Magnolia Warbler. Higbees Beach. 1 September 2010 (Tom Johnson).

Blackpoll Warbler. Higbees Beach. 1 September 2010 (Michael O'Brien).


Location: Cape Island--Higbees Beach SWA--Dike
Observation date: 9/1/10
Notes: light WSW wind, very warm, clear; highlights = Baird's Sandpiper, Yellow-throated Warbler, nice September diversity and overall a good flight. Only species that appeared to be engaged in morning flight are included in this list.
Number of species: 33

Ruby-throated Hummingbird - Archilochus colubris 5
Belted Kingfisher - Megaceryle alcyon 1
Downy Woodpecker - Picoides pubescens 1
Eastern Kingbird - Tyrannus tyrannus 210
Red-eyed Vireo - Vireo olivaceus 18
Red-breasted Nuthatch - Sitta canadensis 18
Blue-gray Gnatcatcher - Polioptila caerulea 12
American Robin - Turdus migratorius 11
Northern Mockingbird - Mimus polyglottos 4
Cedar Waxwing - Bombycilla cedrorum 49
Blue-winged Warbler - Vermivora pinus 1
Tennessee Warbler - Vermivora peregrina 6
Northern Parula - Parula americana 12
Yellow Warbler - Dendroica petechia 27
Chestnut-sided Warbler - Dendroica pensylvanica 5
Magnolia Warbler - Dendroica magnolia 4
Cape May Warbler - Dendroica tigrina 10
Black-throated Blue Warbler - Dendroica caerulescens 4
Black-throated Green Warbler - Dendroica virens 5
Blackburnian Warbler - Dendroica fusca 4
Yellow-throated Warbler - Dendroica dominica 1
Pine Warbler - Dendroica pinus 1
Prairie Warbler - Dendroica discolor 4
Blackpoll Warbler - Dendroica striata 4
Bay-breasted/Blackpoll Warbler - Dendroica castanea/striata 6
Black-and-white Warbler - Mniotilta varia 12
American Redstart - Setophaga ruticilla 264
Ovenbird - Seiurus aurocapilla 1
Northern Waterthrush - Seiurus noveboracensis 45
warbler sp. - Parulinae sp. 83
Savannah Sparrow - Passercula sandwichensis 1
Blue Grosbeak - Passerina caerulea 1
Indigo Bunting - Passerina cyanea 1
Bobolink - Dolichonyx oryzivorus 230
Baltimore Oriole - Icterus galbula 17

This report was generated automatically by eBird v2(http://ebird.org)

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