Survival, Harvest, and Lincoln Estimates of Wood Ducks Banded in Ohio

Abstract Wildlife agencies have carefully managed wood duck Aix sponsa populations in part through harvest regulations since the early 1900s. However, unlike many other waterfowl species in North America, waterfowl managers largely do not know breeding population size. Lincoln–Petersen methods based on harvest and band recovery data are an attractive alternative to air or ground count-based surveys for estimating populations of wood ducks by state and federal agencies that are tasked with sustainably managing harvest opportunities for this species. We used banding and recovery data to estimate annual survival rates, harvest rates, and population size in late summer (August–September) using Lincoln–Petersen methods for wood ducks banded within Ohio from 1990 to 2017. Sex, age, and daily bag limits best explained survival rates of wood ducks banded in Ohio, with lower survival rates in years with more liberal bag limits. Lincoln–Petersen estimates of population size ranged from 116,992 to 632,462 annually, and we detected a significant declining trend in population size through time. Mean harvest rates of wood ducks banded in Ohio ranged from 0.069 (adult females) to 0.121 (hatch-year males), and we detected a significant increasing trend in harvest rate through time for adult male, hatch-year male, and hatch-year female wood duck cohorts. Aerial surveys in other Great Lakes states provide comparable population estimates with our Lincoln–Petersen estimates for Ohio and also show a declining trend in population size. We recommend continued investigation into the use of Lincoln–Petersen techniques for estimating wood duck population size throughout the Great Lakes region. If declining population trends are not unique to Ohio, waterfowl managers may need to further assess the potential impact of increased harvest rates on population size to ensure sustainable harvest into the future.

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Nest parasitism, promiscuity, and relatedness among wood ducks

PLoS ONE ◽

10.1371/journal.pone.0257105 ◽

2021 ◽

Vol 16 (12) ◽

pp. e0257105

Author(s):

Kayla Harvey ◽

Philip Lavretsky ◽

Justyn Foth ◽

Christopher K. Williams

Keyword(s):

Extreme Case ◽

Mitochondrial Control Region ◽

Aix Sponsa ◽

Nest Parasitism ◽

Wood Ducks ◽

Cavity Nesting ◽

Nuclear Loci ◽

Relationship Of ◽

Wood Duck ◽

Do So

Nest parasitism is a common reproductive strategy used by many species of cavity nesting birds. Among these, the wood duck (Aix sponsa) is known to have evolved very specific strategies of when and whom to parasitize that is often based on population and/or environmental queues. Here, we investigated the genetic relationship of two female wood ducks competing over an artificial nesting box in Delaware, including the continued incubation of one female despite the death and body remains of the other female throughout the incubation process. We test whether such an extreme case of nest parasitism can be explained by relatedness, egg lineage composition, or a combination of other factors. To do so, we extracted genomic DNA from blood and tissue of the females, as well as chorioallantoic membranes of all viable and inviable eggs. Subsequently, we assessed relatedness among females and eggs based on hundreds of nuclear loci and the mitochondrial control region. We concluded that (1) the two incubating females were entirely unrelated, (2) the single clutch is in fact represented by a minimum of four unrelated females, and (3) a single female can lay eggs sired by different males. The latter finding is the first direct evidence for successful extra-pair copulation in wood ducks. With decreasing costs and increasing effectiveness, genomic methods have the potential to provide important insights into more complex ecological and evolutionary tactics of such populations.

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Effect of Diet on Visceral Morphology of Breeding Wood Ducks

The Auk ◽

10.1093/auk/101.1.93 ◽

1984 ◽

Vol 101 (1) ◽

pp. 93-98 ◽

Cited By ~ 20

Author(s):

Ronald D. Drobney

Keyword(s):

Food Intake ◽

Dietary Fiber ◽

Diet Quality ◽

Fiber Content ◽

Aix Sponsa ◽

Digestive Organs ◽

Wood Ducks ◽

Mean Size ◽

The Mean ◽

Wood Duck

Abstract Changes in Wood Duck (Aix sponsa) digestive organs reflect adaptations to accommodate changes in diet quality, metabolism, and food intake. The size of the gizzard, intestine, ceca, and liver of males decreased between fall and spring and correlated with a reduction in the fiber content of the diet. The mean size of the intestine, liver, and ceca of hens increased in response to high dietary fiber in fall and hyperphagia during laying. Decreases in the size of digestive organs in hens were associated with reduced feeding during incubation and decreased dietary fiber between fall courtship and prebreeding.

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Combining waterfowl and breeding bird survey data to estimate wood duck breeding population size in the Atlantic Flyway

Journal of Wildlife Management ◽

10.1002/jwmg.938 ◽

2015 ◽

Vol 79 (7) ◽

pp. 1051-1061 ◽

Cited By ~ 10

Author(s):

Guthrie S. Zimmerman ◽

John R. Sauer ◽

Kathy Fleming ◽

William A. Link ◽

Pamela R. Garrettson

Keyword(s):

Population Size ◽

Survey Data ◽

Breeding Population ◽

Breeding Bird Survey ◽

Breeding Bird ◽

Bird Survey ◽

Atlantic Flyway ◽

Wood Duck

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Reproductive Bioenergetics of Wood Ducks

The Auk ◽

10.1093/auk/97.3.480 ◽

1980 ◽

Vol 97 (3) ◽

pp. 480-490 ◽

Cited By ~ 9

Author(s):

Ronald D. Drobney

Keyword(s):

Egg Production ◽

Energy Content ◽

Temporal Distribution ◽

High Energy ◽

High Energy Density ◽

Aix Sponsa ◽

Fat Reserves ◽

Wood Ducks ◽

Large Numbers ◽

Wood Duck

Abstract A model for the daily energy requirements during egg production was developed for Wood Duck (Aix sponsa) hens laying a 12-egg clutch. Reproductive requirements are high, because Wood Ducks lay large clutches of relatively large eggs that have a high energy density. Costs totaled 5,996 kJ and included 2,969 kJ for carbohydrates and lipids, 1,595 kJ for protein, and an estimated 1,432 kJ for biosynthesis. Both are the temporal distribution of costs and the use of stored fat reserves are thought to be important factors enabling hens to meet these large requirements. Costs equivalent to that of an entire egg are incurred for only 6 days during the cycle, because costs are distributed over an 18-day period rather than the 12 days of laying. The energy content of body fat expended by hens was sufficient to account for 88% of the estimated requirements for biosynthesis and the nonprotein fraction of the oviduct and clutch. Protein and minerals are primarily dietary requirements and are obtained by foraging for invertebrates during laying. Although an egg contains only about 5 g of protein, hens must consume large numbers of invertebrates to meet this requirement. The ability to meet most nonprotein requirements with stored fat may therefore be essential to ensure that hens have enough time to forage for invertebrates.

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Seabird breeding population size on the Antarctic Peninsula related to fisheries activities in non-breeding ranges off South America

Antarctic Science ◽

10.1017/s0954102017000207 ◽

2017 ◽

Vol 29 (6) ◽

pp. 495-498 ◽

Cited By ~ 4

Author(s):

Lucas Krüger ◽

Vitor H. Paiva ◽

Maria V. Petry ◽

Jaime A. Ramos

Keyword(s):

South America ◽

Population Size ◽

Antarctic Peninsula ◽

Survival Rates ◽

Breeding Population ◽

Adult Survival ◽

Fishery Discards ◽

Carry Over ◽

Fisheries Interactions ◽

The Antarctic

AbstractPopulation growth of the southern giant petrelMacronectes giganteusfrom South America has been linked with an increase in fishing activities. It was demonstrated recently that a population from Elephant Island, Antarctic Peninsula, largely overlaps its non-breeding distribution with zones of high fishing intensity off South America. This study investigated the assumption that the increase in this population since the 1980s is related to an increase in fisheries off South America. Our results show that the population size is proportional to the increase in demersal and squid fisheries. These fisheries produce a considerable amount of discards, which can be used by non-breeding southern giant petrels as a food source during unfavourable conditions in winter. This may enhance the adult survival rates with potential carry-over effects on population size. Our study shows that we need to further understand the effects of fishery discards/offal on scavenging seabirds of the Southern Ocean, and highlights the importance of understanding the carry-over effects of seabird–fisheries interactions during the non-breeding phase in population dynamics.

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An experimental test of information use by North American wood ducks (Aix sponsa): external habitat cues, not social visual cues, influence initial nest-site selection

10.1101/2020.05.08.084012 ◽

2020 ◽

Author(s):

Elena C. Berg ◽

John M. Eadie

Keyword(s):

Site Selection ◽

Visual Cues ◽

Nest Site ◽

Social Information ◽

Nest Site Selection ◽

Habitat Characteristics ◽

Aix Sponsa ◽

Nest Boxes ◽

Wood Ducks ◽

Wood Duck

AbstractBirds may use a variety of cues to select a nest site, including external information on habitat structure and nest site characteristics, or they may rely instead on social information obtained directly or indirectly from the actions of conspecifics. We used an experimental manipulation to determine the extent to which a California population of the wood duck (Aix sponsa) used social information gleaned from visual cues inside nest boxes that might indicate the quality or occupancy of that site. Over two nesting seasons, we manipulated the contents of newly installed boxes to simulate one of three states: (1) presence of wood duck eggs, indicating current use of a nest site; (2) presence of down and shell membranes, indicating a previously successful nest; and (3) control nests with fresh shavings indicating an unused box. In addition, we measured habitat characteristics of the area surrounding each box to assess the use of external, non-social information about each nest site. We found no evidence that females laid eggs preferentially, or that conspecific brood parasitism was more likely to occur, in any of the treatments. In contrast, nest site use and reproductive traits of wood ducks did vary with vegetation cover, and orientation and distance of the box from water. Our results suggest that personal information, not social information, influence initial nest site selection decisions when females are unfamiliar with a site. Social cues likely become increasingly important once nest sites develop their own history, and a population becomes well established.Significance StatementIn selecting a nest site, birds may use many types of information, including habitat characteristics, their own previous breeding experience, or social cues inadvertently provided by other individuals of the same or different species. We examined information use in a Californian population of wood ducks by experimentally manipulating the visual cues within nest boxes and found that females did not use internal box cues to direct their nesting behaviors, appearing to rely on key habitat characteristics instead. These results contrast with previous studies of this system, suggesting that females may change the cues they use depending on their prior experience with a particular area. In the nest-site selection literature, there appears to be a divergence between research on passerines versus waterfowl, and we advocate unifying these perspectives.

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Utility-Scale Solar in the Great Lakes: Analyzing Community Reactions to Solar Developments

Sustainability ◽

10.3390/su13041677 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1677

Author(s):

Emma Uebelhor ◽

Olivia Hintz ◽

Sarah B. Mills ◽

Abigail Randall

Keyword(s):

Content Analysis ◽

Great Lakes ◽

Energy Production ◽

Community Support ◽

Community Perceptions ◽

Global Impact ◽

Local Newspaper ◽

Great Lakes States ◽

Utility Scale ◽

Newspaper Articles

In the coming years, it is expected that reliance on utility-scale solar projects for energy production will increase exponentially. As a result, communities throughout the Midwest will become potential solar facility hosts. Previous research has sought to identify factors that influence community support and opposition to solar developments throughout the country. This paper builds upon prior research by examining community perceptions about the economic, environmental, local and global impact of solar projects in four Great Lakes states using a content analysis of local newspaper articles. Ultimately, this paper identifies the most common perceptions of solar facilities and offers some preliminary suggestions on strategies to mitigate the most prevalent concerns.

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