Relationships of Food to Spatial and Temporal Breeding Strategies of Mallards in Sweden

Pehrsson, Olof

doi:10.2307/3801164

Cited by 77 publications

(40 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Wetland-related brood survival differences were identified, and wetlands with larger open water area and less nesting habitat were indicated as important for brood-rearing, necessitating the consideration of various life-history stages in habitat use Pöysä 1993, Roy et al 2014). Habitat shifts among breeding stages of other boreal ducks have been demonstrated in European studies (Pehrsson 1984, Nummi and Pöysä 1993, Paasivaara and Pöysä 2008. Importantly, in the fall, juvenile Ring-necked Ducks require wetlands with still different attributes from wetlands used for brood-rearing (Roy et al 2014), further illustrating the importance of considering multiple life-history stages and broader perspectives in conservation.…”

Section: Resultsmentioning

confidence: 99%

“…Koons and Rotella (2003) examined nest success in the Parklands of Manitoba, but the landscape had a minimal forest component. In Minnesota, the last study of Ring-necked Duck nesting success in the forest was during 1978-1984(Roy et al 2012, although a more recent study during [1985][1986][1987] was conducted in the forest-prairie transition (Maxson and Riggs 1996). Elsewhere, nesting vital rate estimates for Ring-necked Ducks are decades old (Mendall 1958, Murdy 1965, Sarvis 1972, McAuley and Longcore 1988, 1989 and preceded the development of statistical methods to compare factors influential to nest survival (Dinsmore et al 2002, Dinsmore andDinsmore 2007).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Nest and brood survival of Ring-necked Ducks in relation to anthropogenic development and wetland attributes

Roy¹

2018

ACE

View full text Add to dashboard Cite

ABSTRACT. The boreal and hemiboreal forests are facing increasing anthropogenic development in areas that have traditionally been remote and inaccessible. Although these forests are recognized as important to breeding waterfowl, breeding season vital rates and the influence of anthropogenic development on these rates remain largely unexplored. I estimated nest and brood survival of Ring-necked Ducks (Aythya collaris) in the hemiboreal forest of Minnesota. I located 115 nests on 43 wetlands, radio-tagged 65 nesting hens, and monitored 32 broods. I considered the influence of distance to and density of buildings and roads, and road-surface type, as well as wetland characteristics and other variables hypothesized to influence waterfowl vital rates. The best-supported nest survival models included covariates for distance from the nest to nearest road and road-surface type. Nest survival declined with increasing distance from roads and was higher for nests near paved roads, at least when the distance was < 400 m. However, an interaction term in the topranked model suggested the effect of road type varied as a function of distance from nest. The model-averaged estimate of 35-day nest survival, based on the top two models was 0.278 (SE = 0.048). Brood survival increased with brood age and open water area, and decreased with nesting habitat area and distance from open water to nearest road. Cumulative brood survival to 30 days was 0.263 (SE = 0.035). These findings indicate that roads may influence both nest and brood survival. Furthermore, higher brood survival at wetlands with less nesting habitat area and more open water area may explain why hens move broods. Conservation managers should consider how habitat needs change throughout the breeding season to adequately address the needs of Ring-necked Ducks. Further study is needed to understand how anthropogenic development can be incorporated into conservation planning. Survie des nids et des couvées de Fuligules à collier en relation avec le développement d'origine anthropique et les caractéristiques des milieux humidesRÉSUMÉ. Les forêts boréales et hémi-boréales subissent une augmentation du développement d'origine anthropique dans des régions qui étaient autrefois éloignées et inaccessibles. Bien qu'on sache que ces forêts sont importantes pour la nidification de la sauvagine, les paramètres vitaux en saison de nidification et l'influence du développement d'origine anthropique sur ce groupe d'oiseaux demeurent grandement inexplorés. Les taux de survie de nids et de couvées de Fuligules à collier (Aythya collaris) ont été estimés dans la forêt hémi-boréale du Minnesota. Cent-quinze nids situés dans 43 milieux humides ont été localisés, 56 femelles nicheuses ont été équipées d'émetteurs radios et 32 couvées ont été suivies. L'effet de la distance et de la densité des bâtiments et des routes ont été examinés, tout comme le type de revêtement des routes, de même que les caractéristiques des milieux humides et d'autres variables pouvant influer les taux de survie de la s...

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Nest and brood survival of Ring-necked Ducks in relation to anthropogenic development and wetland attributes

Roy¹

2018

ACE

View full text Add to dashboard Cite

show abstract

“…Eriksson (1979) showed that broods preferred lakes without fish and that their use of an experimental lake increased after fish were removed. Pehrsson (1 979) showed that the highest rate of food intake in Mallard ducklings occurred on lakes where fish had been removed, and further, by experiment Pehrsson (1984) showed that ducklings obtained more food in lakes where fish had been removed. T h e experiment in the present study showed that high fish density reduced the abundance of emerging chironomids and Ephemeroptera.…”

Section: Discussionmentioning

confidence: 99%

“…Some coarse fish species eat similar invertebrates to Mallard (Eriksson 1979, Pehrsson 1984 and Goldeneye Bucephala clangula ducklings (McAllister Eadie & Keast 1982) and fish removal can result in an increase of certain benthic macroinvertebrates such as some crustacea and members of the family Chironomidae (Eriksson 1979, Gilinsky 1984, Morin 1984.…”

Section: Discussionmentioning

confidence: 99%

“…However, there are marked individual differences in home range size. Recent work has shown that competition with fish for invertebrates could affect brood home ranges (Eriksson 1979, Andersson 1981, McAllister Eadie & Keast 1982, Pehrsson 1984. Fish density could therefore affect duckling survival, particularly on flooded quarries which have been stocked with fish for sport.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Survival of Mallard ducklings Anas platyrhynchos and competition with fish for invertebrates on a flooded gravel quarry in England

Hill¹,

Wright

Street

1987

Ibis

View full text Add to dashboard Cite

The survival of Mallard Anas platyrhynchos ducklings was studied on a complex of flooded gravel quarries in England and their weight changes in response to invertebrate predation by fish were studied by experiment. The majority of duckling loss occurred during the first 12 days after hatching but those feeding on the river where fish were scarce survived better than those feeding on lakes where fish density was high. Duckling mortality was higher in broods with large home ranges. In the experimental trials an increase in fish density was related to a reduction in both the number of emerging invertebrates and the biomass of aquatic macrophytes. Ducklings feeding in these ponds travelled further and gained less weight than on the pond with a low fish density where the number of emerging invertebrates was higher.

show abstract

Correlates of lake use by breeding common scoters in Scotland

Hancock

Robson

Smith

et al. 2015

Aquatic Conservation

View full text Add to dashboard Cite

ABSTRACT1. Many populations of sea-ducks, which typically winter at sea but breed on fresh water, are declining. Numbers of common scoters Melanitta nigra (L.) breeding in Scotland halved between 1995 and 2007, despite most breeding sites having special conservation status. To identify potential conservation measures, a 3-year study was conducted, investigating correlates of lake use by scoters.2. At 26 scoter breeding lakes, food abundance (macroinvertebrates) and foraging habitats (substrates, water depth) were measured, and their associations with scoter lake use explored using multi-model inference. Correlates of macroinvertebrate abundance (water quality, fish abundance) were also investigated.3. Averaged over 3 years (2009 -2011), these lakes held 26.7 (SE 6.3) females, around half the Scottish breeding population. Scoters occurred more often at lakes having abundant large-bodied invertebrates and extensive shallow water. Lakes where the average weight of the largest invertebrate in each sample exceeded 4 mg had 9.2 times (females) or 27 times (broods) more scoter records than other lakes. Lakes where water depths (10 m from the shore) averaged less than 1.3 m had 2.5 times (females) or 12 times (broods) more scoter records than other lakes.4. The abundance of large-bodied invertebrates was greater where small fish species (mostly three-spined sticklebacks Gasterosteus aculeatus) were more common and brown trout Salmo trutta were scarcer.5. Results suggest two approaches to scoter conservation. At lakes used for hydro-electricity generation, water level regimes that provide extensive shallow water should be tested to see if these benefit scoters. At lakes used for trout fishing, trout reduction by increased angling should be trialled, to see if this increases large-invertebrate abundance and scoter use.

show abstract

Relationships of Food to Spatial and Temporal Breeding Strategies of Mallards in Sweden

Cited by 77 publications

References 21 publications

Nest and brood survival of Ring-necked Ducks in relation to anthropogenic development and wetland attributes

Nest and brood survival of Ring-necked Ducks in relation to anthropogenic development and wetland attributes

Survival of Mallard ducklings Anas platyrhynchos and competition with fish for invertebrates on a flooded gravel quarry in England

Correlates of lake use by breeding common scoters in Scotland

Contact Info

Product

Resources

About