NewsAbout UsLife HistoryProgramsLinks Home
Population Monitoring Program

Possessing annual estimates of black duck population characteristics, including abundance, sex and age structure, and vital rates (i.e., survival and recruitment) is critical to fulfilling the mission of the BDJV and achieving the goals of the NAWMP.  These estimates form the basis of black duck adaptive management and allow researchers and managers to assess model predictions, evaluate responses of black ducks to management, and track progress towards NAWMP goals.  Black duck population monitoring consists of three complementary programs: pre-season banding, the Mid-Winter Inventory, and Eastern Breeding Waterfowl Survey. 

Operational Programs Pilot Programs

Monitoring Seasonal Survival Rates (two-season banding program)

Introduction:

The goals of American black duck management are to ensure the future sustainability of the population and provide recreational opportunities, including sport harvest. To meet these goals managers and researchers require information about the abundance and distribution of populations, and vital rates (i.e., survival and mortality rates). Researchers and managers have principally relied on large-scale banding programs to obtain this information. Over the past 2-3 decades researchers and managers have been most interested in obtaining information on annual survival and harvest rates. Given these objectives researchers and managers have typically relied on banding programs consisting of a single banding period just prior to the hunting season (i.e., preseason; July-September) because it is the most efficient design (Brownie 1985, Nichols and Hines 1987). However, single-season banding operations have a variety of constraints. First, preseason banding is not the most logistically or financially efficient season to trap black ducks. Second, single-season banding programs do not provide information about seasonal survival rates thus limit our ability to model and contrast alternative hypotheses of population regulation (e.g., additive harvest mortality vs. post-season density dependence through changes in survival). This second limitation is particularly important because previous research and experience suggest management agencies cannot attain population goals through harvest management alone. Further, predictions of large-scale landscape and system changes (e.g., climate change) may influence the black duck population in ways not experienced or anticipated in harvest management programs. To address current management needs and address the impact of anticipated landscape and system changes on black ducks we need estimates of seasonal survival rates.

Goals and objectives:

The BDJV proposes to implement a 5-year pilot project to assess the potential of a 2-period (pre- and post-hunting season) banding program to estimate seasonal survival and harvest rates. A 2-period banding program will provide data to estimate survival during the summer/fall (August–January) and winter/spring (February–July). It will also provide data to estimate harvest rate analogous to estimates currently obtain from pre-season banding alone. The overall goal of this effort is to improve our ability to model black duck population dynamics and identify limiting factors that can be mitigated through habitat and harvest management. Our objectives are:
1. Use historic banding data to design protocols (i.e., season specific sample sizes and spatial allocation) that will provide point estimates of seasonal survival and harvest rates with annual coefficient of variation =10% and 5-year mean coefficient of =5%. 2. Implement 5-year pilot effort to test field and data analysis protocols. Resulting banding data will be used to evaluate success of field operations (i.e., meeting banding quotas), assumptions, data quality and applicability. 3. Use data from pilot effort to estimate required post-season banding sample needed to measure density dependent changes in post-season survival. 4. Revise protocols and make recommendations for operational implementation of 2-season banding program for American black ducks.

Monitoring Seasonal Survival Proposal

ABDU Winter Banding Protocol 2010/2011

Preliminary Report ABDU Winter Banding 2011

ABDU Winter Banding in Ontario Releasing a banded black duck ABDU Banding in NJ
Winter banding in Ontario. (photo credit: Anonymous). Canadian Wildlife Service Biologists releasing a banded black duck in Ontario, 2011. (photo credit: Canadian Wildlife Service). Black ducks captured during banding operations in New Jersey, 2011. (photo credit P. Devers).
Winter banding in Maine
Snow damage to a duck trap in Maine, Winter 2011. (photo credit: K. Sullivan).

Pilot Project: Banding moulting males in Ontario’s Hudson Bay Lowlands

The BDJV has provided support to the Ontario Ministry of Natural Resources to test field methodology to capture moulting male black ducks in northern Ontario.  The objective is to determine the feasibility of increasing the number of adult black ducks banded in Ontario annually by targeting moulting birds known to gather in the Hudson Bay Lowlands.  Biologists intend to increase the banded total in Ontario by 300-500 per year to help balance the continental distribution of banded black ducks and improve estimates of vital rates.

Assessing methodology to estimate black duck pre-hunting season age ratios

- Are Ratio Working Group

-Age Ratio Working Group Report 2011