DUCK NUMBERS

 
The picture is a little confusing this year as a couple of traditional and expected patterns are not apparent in the results. For one, the May Pond count is up by 18% over the estimated number in 2000. This is despite the very dry conditions in Alberta and southwest Saskatchewan. The pond numbers are up strongly in Southern Manitoba (+69%) and the Eastern Dakotas (+41%), as our staff has reported all along. Contrary to the historical pattern though, the total number of breeding waterfowl declined by 14% from last year, down to 36.1 million birds from 42 million in 2000. Normally, we see pond and total duck numbers moving in the same direction so this is an unusual result. Overall, most species have declined - and I think more than most of us would have anticipated.  The data show decreased total duck numbers in all regions except Southern Manitoba, which, unfortunately, is not a very large portion of the breeding grounds. North Dakota decreased slightly (-8%) but not significantly.

Overall the declines are driven by Southern Saskatchewan, Southern Alberta, Northern Saskatchewan, Northern Manitoba, and the region that includes Northern British Columbia, Central and Northern Alberta and the Northwest Territories. The low counts in the north are contrary to the typical pattern. Normally when the ducks are down on the prairies, they tend to increase, or at least stay stable in the north as many birds that are displaced are counted there. Habitat in those northern regions is considered to be in good condition this year. The survey was delayed there because of bad weather and that may offer a partial explanation. It could be that the late survey found more birds that had stopped breeding activity and were found in larger flocks that have less influence on breeding population estimates.

The attached table summarizes the duck counts for the 10 main species. The most unexpected result in these data is that pintails actually show an increase in numbers, although it is statistically insignificant. I’m sure pintail watchers expected the pattern to be just the opposite. They went from 2.9 million last year to 3.2 million in 2001 but are still 41% below the North American Plan goal. This is a welcome change from the pattern of the past few years. The migration study that we are conducting showed that more pintails from California moved to the Dakotas and the wet parts of Saskatchewan than they did last year. We also know from our nesting studies in North and South Dakota that pintails are putting forth a tremendous nesting effort and in higher numbers than last year. Wetland conditions are excellent in the Eastern Dakotas. These new survey data fall in line with those independent observations as the increase in pintails is very much driven by southern Saskatchewan (+47%), Southern Manitoba (+117%) and the Eastern Dakotas (+93%). Numerically, the Dakotas show the greatest increase of all three of these areas. Thus, the long-held view of the pintail being a species that is able to move to areas that have good spring water seems to be demonstrated this year. Ironically, we have more pintails than we’ve seen for several years in the best prairie habitat so their numbers should actually go up.

Mallards have gone down by 17%, from 9.5 million to 7.9 million birds and are 3% below the North American Plan goal for the first time since 1996. Their pattern of change pretty well reflects that described above for total ducks. Southern Manitoba (+21%) is the only place where they increased. Except for the Eastern Dakotas (no change) all other prairie strata went down - correlated with the drought in the west but a different pattern than that shown for pintails, which are also early nesters. The counts are down across the north. There does appear to be a widespread and real decline although, again, the northern numbers are a surprise.

The other species are all down by similar amounts. Gadwall are down significantly (-15%), from 3.2 to 2.8 million. Their decline is driven by a 38% drop in the Eastern Dakotas but they are up everywhere else, although not significantly, except southern Alberta. I cannot offer an explanation as to why Gadwall are down in the Dakotas when the water and cover conditions are so excellent. They remain 76% above the goal.

Wigeon are down by 9% although this result is not statistically significant. Nevertheless, wigeon are now solidly again in the small group of three species that are well below (-16%) the goals of the North American Waterfowl Management Plan (Scaup (-41%) and Pintails (-41%) are the other two).

Shovelers, at 3.3 million, are not significantly different than last year (3.5 million) although they did show a marked increase of +39% in the Eastern Dakotas, as we would have expected given the habitat conditions there.

Green-winged Teal declined by 21%, from 3.2 to 2.5 million. They are still 36% above the North American Plan goal. They declined in most areas although the greatest influence on the count was a 42% decline in the Northwest Territories, Northern B.C. and Northern Saskatchewan where over half a million fewer birds than last year were counted.

Blue-winged Teal decreased by 23% to 4.7 million birds. They remain at 24% over the North American Plan goal. Similar to Gadwall, their decline is driven mostly by a 24% decrease, over a million birds, in the Eastern Dakotas. This defies our expectations for Blue-wings in that region, as wetland and nesting cover conditions appear to be excellent. However, note that it is generally wetter across more southern areas where Blue-wings have been known to stop in the past to nest outside the surveyed area. Some birds may be accounted for in those regions.

Redheads (-23%) and Canvasbacks (-18%) both declined by similar amounts. At 712,000 birds the redhead is still 11% above the goal but is over 200,000 birds lower than last year. This statistically significant decrease is almost completely accounted for by declines in Alberta, Saskatchewan and the Eastern Dakotas. As speculated for blue-winged teal, some redheads may have stopped further south outside the surveyed area. They have much lower homing rates than most other divers. The Canvasback declined by 125,000 birds although this is not statistically significant. It is 8% above its goal at 580,000 birds. Nevertheless, the overall patterns for the continental populations of these diver species are slipping downwards.

Scaup are again numerically down by 8% over last year although the change from 4.0 million to 3.7 million is not statistically significant. However, the long-term pattern of failing to recover from the low numbers reached in the early 1990s continues and Scaup are still 41 % below the North American Plan goal. This remains as one of our highest priorities for new studies to help us figure out what is going on with this species.

In the east, the total duck count was almost identical to last year at 3.3 million birds. The only significant change was a decline of Ring-necked Ducks by 43% from 619,000 to 353,000. The reason for this is not apparent as Ring-necks have generally been increasing across their range for several years. Habitat conditions remain excellent across the eastern areas so we would anticipate that production should be fine throughout the east.

This survey does not provide much information about conditions across theArctic. Spring weather conditions were not favorable for early nesting so a reduced flight of ducks and geese from Alaska is expected. In the east, it appears that weather conditions may be ideal for eastern Arctic geese. We have been concerned for some time about the Atlantic Flyway Population of Canada Geese which nest primarily on the Ungava Peninsula of Quebec. It has been very warm and favorable for the geese there. Nesting numbers are higher than they have been since the early 1990s, predation appears to be low, clutch sizes are larger than normal and hatch rates are very good. This population will almost certainly undergo a significant recovery this breeding season. We don’t yet have very much information back on the other portions of the Arctic.

 

Table 1. Duck breeding population estimates (x 1,000) in the traditional survey area (May / June 2001)

Species 2000 2001 NAWMP Goal % Change From 2000 % Change from NAWMP Goals

Mallard 9,470 *7,904 8,122 -17 -3

Gadwall 3,158 *2,679 1,518 -15 +76

Wigeon 2,733 2,494 2,953 -9 -16

GW Teal 3,194 *2,509 1,843 -21 +36

BW Teal 7,431 *5,757 4,654 -23 +24

Shoveler 3,521 3,314 1,985 -6 +67

Pintail 2,908 3,296 5,597 +13 -41

Redhead 926 *712 640 -23 +11

Canvasback 707 580 538 -18 +8

Scaup 4,026 3,694 6,250 -8 -41