Avoiding perceived past resource use of potential competitors affects niche dynamics in a bird community

Abstract

BackgroundSocial information use is usually considered to lead to ecological convergence among involved con- or heterospecific individuals. However, recent results demonstrate that observers can also actively avoid behaving as those individuals being observed, leading to ecological divergence. This phenomenon has been little explored so far, yet it can have significant impact on resource use, realized niches and species co-existence. In particular, the time-scale and the ecological context over which such shifts can occur are unknown. We examined with a long-term (four years) field experiment whether experimentally manipulated, species-specific, nest-site feature preferences (symbols on nest boxes) are transmitted across breeding seasons and affect future nest-site preferences in a guild of three cavity-nesting birds.ResultsOf the examined species, resident great tits (Parus major) preferred the symbol that had been associated with unoccupied nest boxes in the previous year, i.e., their preference shifted towards niche space previously unused by putative competitors and conspecifics.ConclusionsOur results show that animals can remember the earlier resource use of conspecifics and other guild members and adjust own decisions accordingly one year after. Our experiment cannot reveal the ultimate mechanism(s) behind the observed behaviour but avoiding costs of intra- or interspecific competition or ectoparasite load in old nests are plausible reasons. Our findings imply that interspecific social information use can affect resource sharing and realized niches in ecological time-scale through active avoidance of observed decisions and behavior of potentially competing species.

Heterospecific Nest Site Copying Behavior in a Wild Bird: Assessing the Influence of Genetics and Past Experience on a Joint Breeding Phenotype

“…2 m and the two boxes received different symbols. This allowed settling flycatchers to choose between symbols independently from other characteristics of the microhabitat Seppänen et al, 2011;Loukola et al, 2012;Forsman et al, 2014). Here, we used a single-box design to be able to conduct our experiment over large spatial and temporal scales, but the choice of a nest box could in this case be associated not only with the symbol but also with other microhabitat characteristics around the box.…”

“…Repeatability was estimated as the ratio between the individual variance and the total variance plus 1 for the probit link function (Nakagawa and Schielzeth, 2010). Using a similar approach, we also estimated individual repeatability in the probability to choose a specific symbol (either circle or triangle), to test for a potential innate preference for a natural round shape (Forsman et al, 2014).…”

“…Over 5 years, we experimentally provided individuals with a source of social information independent from actual site quality using an artificial nest site feature design previously successfully used in this system Seppänen et al, 2011;Jaakkonen et al, 2013Jaakkonen et al, , 2015Forsman et al, 2014). Using a quantitative genetic approach , we simultaneously explored the relative contribution of female and male (i) overall experience (age, familiarity with the environment, previous experience with the experimental design, and previous breeding success) and (ii) direct and indirect additive genetic effects on the joint decision to use the manipulated information source for nest site choice.…”

Who is in the neighborhood? Conspecific and heterospecific responses to perceived density for breeding habitat selection

“…Instead, social information use appeared to cause positive density‐dependent habitat selection. Few study systems take density into account when testing settlement responses to social cues (Forsman et al., , , ). Understanding the interplay between social information use and density‐dependent habitat selection is critical to better predict when attraction to social cues should occur, and what ultimate mechanisms (such as positive density‐dependent effects on reproduction) drive conspecific and heterospecific attraction alike.…”

Frugivory and seed dispersal of Solanum granuloso-leprosum Dunal (Solanaceae) by birds in deciduous seasonal forest

“…For example, Tangara sayaca, T. preciosa and P. bonariensis removed more fruits during similar time intervals (mid-afternoon), which may have been due to the increased morning activity of Saltator similis, the more dominant and aggressive species. This overlap in resource use results in intra and interspecific competition and division of resources, which may affect the realized niches of coexisting species (Forsman et al, 2014).…”