Sixty-years of community-science data suggest earlier fall migration and short-stopping of waterfowl in North America

Abstract

Worldwide, migratory phenology and movement of many bird species is shifting in response to anthropogenic climate and habitat changes. However, due to variation among species and a shortage of analyses, changes in waterfowl migration, particularly in the fall, are not well understood. Fall migration phenology and movement patterns dictate waterfowl hunting success and satisfaction, with cascading implications on economies and support for habitat management and securement. Using 60 years of band recovery data for waterfowl banded in the Canadian Prairie Pothole Region (PPR), we evaluated whether fall migration timing and/or distribution changed in Mallard (Anas platyrhynchos), Northern Pintail (A. acuta), and Blue-winged Teal (Spatula discors) between 1960 and 2019. We found that in the Midcontinent Flyways, Mallards and Blue-winged Teal migrated faster in more recent time periods, whereas Northern Pintail began fall migration earlier. In the Pacific Flyway, Mallards began fall migration earlier. Both Mallards and Northern Pintails showed evidence of short-stopping in the Midcontinent Flyways. Indeed, the Mallard and Northern Pintail distribution of band recovery data shifted 180 km and 226 km north, respectively, from 1960 to 2019. Conversely, Blue-winged Teal recovery distributions were consistent across years. Mallards and Northern Pintails also exhibited an increased proportion of band recoveries in the Pacific Flyway in recent decades. We provide clear evidence that the timing and routes of fall migration have shifted over the past 6 decades, but these phenological and spatial shifts differ among species. We suggest that using community-science data collected by hunters themselves to explain one of the group’s major concerns (changes in duck abundance at traditional hunting grounds), within the environmental lens of climate change, may help lead to further engagement and two-way dialogue to support effective waterfowl management for these culturally and ecologically important species.

On the need and difficulty of evaluating management strategies improving species persistence

“…In our study (Gaget et al (2024), we found that ducks contribute less than other species to waterbird community adjustment to climate warming. The main hypothesis was that hunting-oriented management may increase the site fidelity of hunted species and thus reduce their distribution change.…”

“…We thank Santangeli (2024) and Navedo (2024) for promoting discussion and brainstorming around the conclusions of our paper (Gaget et al, 2024).…”

“…response to climate change has been assessed at species-specific and continental scale (Cox et al, 2023), and baiting is not practiced as it is in Europe. In comparison to the velocity of climate warming, duck range shift and hunting practices between the two continents might provide additional knowledge to understand how management practices can influence species responses to climate warming at a broad scale.…”

“…Conversely, promoting persistence could also lead to maladaptation, with possibly harmful consequences on long-term species conservation (Navedo, 2024). In Gaget et al (2024), we did not aim to answer the untrivial question of persistence and did not advocate management measures that prevent waterfowl from adapting to climate change. Management actions taken by waterfowl hunters in southern Europe might have diverse consequences for waterbirds and wetlands ecosystems.…”

“…Further investigations would be needed to assess species-specific adaptation interventions and their effects on non-targeted species. As suggested by Gaget et al (2024), habitat management dedicated to duck species can also influence the response to climate warming of species sharing similar ecological requirements. We encourage research on adaptation interventions, including investigating their side effects on other organisms and ecosystem functions.…”