The intensity of interference varies with resource density: evidence from a field study with snow buntings, Plectrophenax nivalis

Intake rates of snow buntings feeding on artificial seed patches were measured at different bird densities, for each of two different seed densities. Interference occurred in the low seed-density treatment, with intake rates declining at high bird densities. However, interference was not found in the high seeddensity treatment. The finding that the strength of interference may depend on resource density contradicts the hypothesis that the functional response is ratio-dependent (Arditi and Akçakaya 1990). The formulation for interference from Hassell and Varley (1969), and the models of Beddington (1975), Ruxton et al. (1992) and Holmgren (1995), also assume that the strength of interference is independent of resource density. The development of behaviour-based models that consider the relation between the intensity of interference, resource density and individual state may provide a more accurate description of the process of interference.

[1]  N. Metcalfe,et al.  Relationships between social status, otolith size at first feeding and subsequent growth in Atlantic salmon (Salmo salar) , 1992 .

[2]  P. Monaghan.  Dominance and dispersal between feeding sites in the herring gull (Larus argentatus) , 1980, Animal Behaviour.

[3]  J. Krebs,et al.  INDIVIDUAL DECISIONS AND THE DISTRIBUTION OF PREDATORS IN A PATCHY ENVIRONMENT , 1988 .

[4]  Donald L. DeAngelis,et al.  A Model for Tropic Interaction , 1975 .

[5]  J. Beddington,et al.  Mutual Interference Between Parasites or Predators and its Effect on Searching Efficiency , 1975 .

[6]  William J. Sutherland,et al.  Field estimates of the strength of interference between oystercatchers haematopus ostralegus , 1982, Oecologia.

[7]  K. Kotrschal,et al.  Food exploitation by a winter flock of greylag geese: behavioral dynamics, competition and social status , 1993, Behavioral Ecology and Sociobiology.

[8]  M. Hassell,et al.  New Inductive Population Model for Insect Parasites and its Bearing on Biological Control , 1969, Nature.

[9]  R. Smith.  Age determination, wing‐feather colour and wing‐length change in Snow Buntings Plectrophenax nivalis , 1992 .

[10]  J. Ekman.  Density-dependent seasonal mortality and population fluctuations of the temperature-zone willow tit (Parus montanus) , 1984 .

[11]  Ralph T. Clarke,et al.  Deriving population parameters from individual variations in foraging behaviour. II: Model tests and population parameters , 1995 .

[12]  John R. Krebs,et al.  INDIVIDUAL DECISIONS AND THE DISTRIBUTION OF PREDATORS IN A PATCHY ENVIRONMENT. II. THE INFLUENCE OF TRAVEL COSTS AND STRUCTURE OF THE ENVIRONMENT , 1991 .

[13]  Sidney A. Gauthreaux,et al.  The Ecological Significance of Behavioral Dominance , 1978 .

[14]  William J. Sutherland,et al.  Deriving population parameters from individual variations in foraging behaviour. I: Empirical game theory distribution model of oystercatchers Haematopus ostralegus feeding on mussels Mytilus edulis , 1995 .

[15]  R. Arditi,et al.  Coupling in predator-prey dynamics: Ratio-Dependence , 1989 .

[16]  Donald L. DeAngelis,et al.  A MODEL FOR TROPHIC INTERACTION , 1975 .

[17]  R. Arditi,et al.  Underestimation of mutual interference of predators , 1990, Oecologia.

[18]  William J. Sutherland,et al.  Aggregation and the `ideal free ` distribution , 1983 .

[19]  R. Clarke,et al.  Rates of food intake and aggression of oystercatchers Haematopus ostralegus on the most and least preferred mussel Mytilus edulis beds of the exe estuary , 1984 .

[20]  G. A. Parker,et al.  Ideal free distributions when individuals differ in competitive ability: phenotype-limited ideal free models , 1986, Animal Behaviour.

[21]  N. Holmgren.  The ideal free distribution of unequal competitors: predictions from a behaviour-based functional response , 1995 .

[22]  Thomas Caraco,et al.  Time Budgeting and Group Size: A Test of Theory , 1979 .

[23]  M. C. Baker,et al.  Foraging success in junco flocks and the effects of social hierarchy , 1981, Animal Behaviour.

[24]  P. Dolman,et al.  Combining behaviour and population dynamics with applications for predicting consequences of habitat loss , 1994, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[25]  J. Ekman.  Alliances in winter flocks of willow tits; effects of rank on survival and reproductive success in male-female associations , 1990, Behavioral Ecology and Sociobiology.

[26]  G. Ruxton,et al.  Interference and Generation Cycles , 1992 .

[27]  J. Goss‐Custard,et al.  Competition for Food and Interference among Waders , 2015 .