Partial aerial survey results in for ducks

The November aerial survey for ducks has been completed for southern regions of the state. Although the 1.3 million ducks estimated on this survey is the highest since 2017, and is up from last November’s record low estimate (855,000), it is still lower than the most recent 5-year (1.5 million) and 10-year (1.7 million) averages. Despite Hurricane Ida’s path through the SE marshes in late-August, both coastal regions showed increased bird numbers from last year. Estimates in SW and SE LA (Figure 2) are up 57% and 19% respectively. The 87,000 birds on Catahoula Lake is a marked increase from last year (12,000), and is above its 5-year (84,000) but below its 10-year (98,000) average.

The NW and NE surveys will be flown early next week. This report will be amended and resent when those data are added.

Though the overall duck estimate was up, this survey marked record low November counts for both gadwall and mottled duck. Unchanged from the September 2021 estimate of 18,000 mottled ducks, this year’s estimate declined from 27,000 last November, 19,000 in 2019, and is down 72% from the long-term November average (64,000). Mottled duck estimates have typically been lower for the September surveys, and counts lower than 18,000 occurred in September 2015, 2016, 2018, and 2019. The lowest being 12,000 birds in September 2016. The gadwall estimate (243,000) declined 16% from the 2020 estimate of 288,000 and was 70% below the long term average (818,000). The most recent 5-year average for gadwall is 603,000.

More mallards (20,000) were observed than any November since 2014 (also 20,000), and the most recent year to top 20,000 mallards was 49,000 in 2010. Alternatively, fewer scaup have not been estimated since 2015 when only 2,000 were observed.

SW Louisiana

Habitat conditions in the SW LA marshes were above average as emergent vegetation has recovered considerably from last year’s hurricane damage, especially east of Calcasieu Lake. Invasive aquatics are also less abundant than just a few years ago. However, submerged aquatic vegetation (SAV) remains spotty in the marsh ponds across many areas of SW LA. Saline and brackish marshes also appeared normal but bird abundance was low from Marsh Island to Rockefeller were flyover occurred during the low tide and mudflats were more abundant than pools. Thus, only the channels held water suitable for ducks where few mottled ducks and gadwalls were observed. The entirety of the agricultural area in this region was extraordinarily dry. A large number of acres were dry and either disked and leveled or standing stubble. Those with water were either thick with 2nd crop rice or devoid of vegetation. The lack of any substantial rain in the last month has not benefitted these habitats as the region has seen less than 2 inches of rain since the beginning of October, most coming during one rain event late in the month and water apparently soaked in without pooling.

Consequently, very few birds were observed in any agricultural fields. The highest concentrations of ducks in SW LA were observed in marshes in and around Rockefeller Refuge and west of White Lake. In addition, a single flock of a few thousand black-bellied whistling ducks (not included in the estimate) was observed south of Lake Arthur and less than 200 white-fronted geese were observed throughout the survey.

SE Louisiana

Eighty-eight percent of all birds were observed on two of the ten transect lines in SW LA, lines 20 and 27. Major impacts of Hurrican Ida were observed in Terrebonne and Barataria Bays between lines 21 (west of Houma) and 24 (North of Grand Isle). Saltwater damage to vegetation, in addition to broken pieces of marsh scattered widely, and a near total absence of SAV characterized the marshes in these Bays. Very few birds other than coots were observed from line 21 to 24. Marsh damage decreased and bird numbers increased farther east, and by line 26 north of Buras SAV was again present in the isolated marsh ponds that were more protected from wind and wave action. The mouth of the Mississippi River looked virtually non-impacted by Ida. Excluding coots, which made up more than half the birds on line 20, more ducks were observed on line 27 at the mouth of the river.

Catahoula Lake
Blue-winged teal declined by 33% from the September survey at Catahoula Lake. Pintails, however have steadily increased since early October and made up over 70% of the birds observed as water level across the lake was ideal for dabblers (28.5 center of lake) though still a foot below target level for opening day. Though there was considerable activity on the lake at the time, birds were observed throughout much of the lake that remained undisturbed. Duck forage on the lake is above average as large areas of millet, sedge, duck potato, and duck salad were observed during vegetation surveys in mid-October.

Although the southern Canadian prairies have begun to freeze, near-term future forecasts for northern tier states continue to show daytime highs well above freezing despite occasional dips into the 20’s and teens at night, and mid-latitude states may maintain highs in the 50’s for some time. Survey and hunting reports in states farther up the flyway have been below average to average. Notwithstanding the drought in the prairie breeding area, mild weather to the north, a dry fall in Louisiana, and hurricane impacted coastal area, this survey is better than would’ve been expected.