3/19/2007

2007 Midwinter Waterfowl Survey Records Historic Low For Canvasbacks

ANNAPOLIS— Each winter, ducks, geese and swans are counted along Maryland’s Chesapeake Bay shoreline and Atlantic coast during the Midwinter Waterfowl Survey. The survey is conducted by pilots and biologists from the U.S. Fish and Wildlife Service and Maryland Department of Natural Resources.

The 2007 survey was flown between December 27, 2006 and January 4, 2007. A total of 478,900 birds were counted, which was a substantial decrease from last year’s count of 577,100. This year tributaries and bays along the Chesapeake were completely ice-free. Since the Maryland Midwinter Waterfowl Survey only covers the tidal, estuarine waters, it is likely that many ducks and geese remained inland on open freshwater reservoirs, lakes and ponds that are normally ice covered.

The Midwinter Waterfowl Survey is conducted at the same time each winter in each state in the Atlantic Flyway, from Maine to Florida. When pooled with the results from other states, the Midwinter Waterfowl Survey provides a long-term measure of the distribution and population size for waterfowl species wintering in the Atlantic Flyway. The survey is especially helpful in tracking the population size of Eastern population tundra swans and Atlantic Brant for which breeding ground surveys are not done.

Low numbers were recorded for several diving ducks this year as well. Most notable was a record low count of Canvasbacks (13,800), down 20,100 from 33,800 in 2006. The previous low count of Canvasbacks was from 1988 when only 23,200 were recorded. Scaup (25,700) showed a substantial decrease, down 53,800 from 2006 (79,500). Mergansers (1,700) also decreased markedly from 2006 (7,000). The low number of diving ducks was probably related to the warm winter and ducks remaining north of traditional wintering areas. High counts of canvasbacks, scaup, long-tailed ducks, redheads, and mergansers were recorded during the Midwinter Waterfowl Survey of the Great Lakes where habitats were relatively ice-free this January.

In Maryland, mallard numbers were greater during 2007 (39,700) than in 2006 (32,500). The number of black ducks counted in 2007 (13,800) was similar to 2006 (13,300), but the 2007 count was substantially below counts made prior to 2005.

Canada goose numbers (285,700) were slightly below the 305,400 counted in 2006. The tundra swan count (8,700) was similar to the record low of 8,200 in 2006. Recent banding studies have shown that tundra swans spend less time in Chesapeake Bay and most now winter further south in North Carolina.

The Maryland Midwinter Survey numbers from 2003 – 2007 are listed below.
 

Species	2003		2004	2005	2006	2007
Mallard	39,000		48,200	52,800	32,500	39,700
Black Duck	22,500		31,700	23,600	13,300	13,800
Gadwall	3,700		2,500	1,400	1,200	1,400
Widgeon	800		6,000	2,000	300	400
G-W Teal	1,000		1,200	1,000	400	3,300
Shoveler	0		100	100		100
Pintail	1,300		4,600	1,900	2,500	500
Total Dabblers	68,400		94,300	82,800	50,300	59,200
Redhead	5,100		6,100	9,300	1,800	1,100
Canvasback	40,000		30,800	39,400	33,800	13,700
Scaup	66,600		106,300	189,800	79,500	25,700
Ring-neck	300		200	1,000	500	900
Goldeneye	2,100		1,000	3,000	700	700
Bufflehead	13,100		9,800	22,000	11,800	12,000
Ruddy Duck	42,700		34,000	36,100	12,100	19,800
Total Divers	169,900		188,200	300,600	140,200	73,900
Scoters	2,300		8,100	40,600	10,000	2,100
Long-tailed Duck	100		400	4,100	700	500
Mergansers	6,500		18,700	5,100	7,000	1,700
Total Ducks	247,300		215,400	433,200	208,400	137,400
Brant	1,500		1,300	1,700	2,400	500
Snow Goose	75,600		93,900	54,900	49,200	46,600
Canada Goose	452,900		355,200	383,400	305,400	285,700
Tundra Swan	15,100		17,900	13,200	8,200	8,700
Total Waterfowl	798,000		781,300	889,900	577,100	478,900