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Pusey, A. E. (1987). Sex-biased dispersal and inbreeding avoidance in birds and mammals. Trends. Ecol. Evol, 2(10), 295–299.
Abstract: Sex differences in dispersal distance are widespread in birds and mammals, but the predominantly dispersing sex differs consistently between the classes. There has been persistent debate over the relative importance of two factors -- intrasexual competition and inbreeding avoidance -- in producing sex-biased dispersal, and over the sources of the difference in dispersal patterns between the two classes. Recent studies cast new light on these questions.
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Dingemanse, N. J., & de Goede, P. (2004). The relation between dominance and exploratory behavior is context-dependent in wild great tits. Behav. Ecol., 15(6), 1023–1030.
Abstract: Individual differences in personality affect behavior in novel or challenging situations. Personality traits may be subject to selection because they affect the ability to dominate others. We investigated whether dominance rank at feeding tables in winter correlated with a heritable personality trait (as measured by exploratory behavior in a novel environment) in a natural population of great tits, Parus major. We provided clumped resources at feeding tables and calculated linear dominance hierarchies on the basis of observations between dyads of color-ringed individuals, and we used an experimental procedure to measure individual exploratory behavior of these birds. We show that fast-exploring territorial males had higher dominance ranks than did slow-exploring territorial males in two out of three samples, and that dominance related negatively to the distance between the site of observation and the territory. In contrast, fast-exploring nonterritorial juveniles had lower dominance ranks than did slow-exploring nonterritorial juveniles, implying that the relation between dominance and personality is context-dependent in the wild. We discuss how these patterns in dominance can explain earlier reported effects of avian personality on natal dispersal and fitness.
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Hildenbrandt, H., Carere, C., & Hemelrijk, C. K. (2010). Self-organized aerial displays of thousands of starlings: a model. Behav. Ecol., 21(6), 1349–1359.
Abstract: Through combining theoretical models and empirical data, complexity science has increased our understanding of social behavior of animals, in particular of social insects, primates, and fish. What are missing are studies of collective behavior of huge swarms of birds. Recently detailed empirical data have been collected of the swarming maneuvers of large flocks of thousands of starlings (Sturnus vulgaris) at their communal sleeping site (roost). Their flocking maneuvers are of dazzling complexity in their changes in density and flock shape, but the processes underlying them are still a mystery. Recent models show that flocking may arise by self-organization from rules of co-ordination with nearby neighbors, but patterns in these models come nowhere near the complexity of those of the real starlings. The question of this paper, therefore, is whether such complex patterns can emerge by self-organization. In our computer model, called StarDisplay, we combine the usual rules of co-ordination based on separation, attraction, and alignment with specifics of starling behavior: 1) simplified aerodynamics of flight, especially rolling during turning, 2) movement above a “roosting area” (sleeping site), and 3) the low fixed number of interaction neighbors (i.e., the topological range). Our model generates patterns that resemble remarkably not only qualitative but also quantitative empirical data collected in Rome through video recordings and position measurements by stereo photography. Our results provide new insights into the mechanisms underlying complex flocking maneuvers of starlings and other birds.
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Connor, R. C. (1995). Altruism among non-relatives: alternatives to the 'Prisoner's Dilemma'. Trends Ecol Evol, 10(2), 84–86.
Abstract: Triver's model of reciprocal altruism, and its descendants based on the Prisoner's Dilemma model, have dominated thinking about cooperation and altruism between non-relatives. However, there are three alternative models of altruism directed to non-relatives. These models, which are not based on the Prisoner's Dilemma, may explain a variety of phenomena, from allogrooming among impala to helping by non-relatives in cooperatively breeding birds and mammals.
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Meriggi, A., & Lovari, S. (1996). A Review of Wolf Predation in Southern Europe: Does the Wolf Prefer Wild Prey to Livestock? J. Appl. Ecol, 33, 1561–1571.
Abstract: 1. The recent recovery of the wolf in southern Europe has not yet removed the risk
of local extinction. Wolf populations are fragmented and often comprise fewer than
500 individuals. In North America, northern and eastern Europe, wolves feed maiiily
on wild herbivores. In southern Europe, this canid has apparently adapted to feed
also on fruit, rubbish, livestock, small and medium-size mammals.
2. The main conservation problem lies with predation o n domestic ~ingulates,w liich
leads to extensive killing of wolves. The reintroduction of wild large herbivores has
been advocated as a means of reducing attacks on livestock, but predatiori on the
latter may remain high if domestic ungulates are locally abundant.
3. Our synthesis of 15 studies, published in the last 15 years, on food habits of the
wolf in southern Europe, has shown that ungulates have been the main diet component
overall. A significant inverse correlation was found between the occurrence (%) of
wild and domestic ungulates in the diet. The presence of relatively few wild ungulate
species was necessary to reduce predation on livestock.
4. Selection of wild and domestic ungulate prey was influenced mainly by their local
abundance, but also by their accessibility. Feeding dependence on rubbish was local
and rare. In Italy, the consumption of riibbish/fruit and that of ungulates was significantly
negatively correlated. Diet breadth increased as the presence of large prey
in tlie diet decreased.
5. The simultaneous reintroduction of severa1 wild ungulate species is likely to reduce
predation on livestock and may prove to be one of the most effective conservation
measures.
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Ronnenberg, K., Habbe, B., Gräber, R., Strauß, E., & Siebert, U. (2017). Coexistence of wolves and humans in a densely populated region (Lower Saxony, Germany). Basic. Appl. Ecol., 25, 1–14.
Abstract: Since the first sporadic occurrences of grey wolves (Canis lupus) west of the Polish border in 1996, wolves have shown a rapid population recovery in Germany. Wolves are known to avoid people and wolf attacks on humans are very rare worldwide. However, the subjectively perceived threat is considerable, especially as food-conditioned habituation to humans occurs sporadically. Lower Saxony (Germany) has an exceedingly higher human population density than most other regions with territorial wolves; thus, the potential for human-wolf conflicts is higher. Using hunters' wildlife survey data from 455 municipalities and two years (2014-2015) and data from the official wolf monitoring (557 confirmed wolf presences and 500 background points) collected between 2012-2015, grey wolf habitat selection was modelled using generalized additive models with respect to human population density, road density, forest cover and roe deer density. Moreover, we tested whether habitat use changed in response to human population and road density between 2012/2013 and 2014/2015. Wolves showed a preference for areas of low road density. Human population density was less important as a covariate in the model of the survey data. Areas with higher prey abundance (5-10 roe deer/km2) and areas with >20% forest cover were preferred wolf habitats. Wolves were mostly restricted to areas with the lowest road and human population densities. However, between the two time periods, avoidance of human density decreased significantly. Recolonization of Germany is still in its early stages and it is unclear where this process will halt. To-date authorities mainly concentrate on monitoring measures. However, to avoid conflict, recolonization will require more stringent management of wolf populations and an improved information strategy for rural populations.
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Preiszner, B., Vincze, E., Seress, G., Papp, S., Bókony, V., Liker, A., et al. (2013). Necessity or capacity? Physiological state predicts problem-solving performance in house sparrows. Behav. Ecol., 25(1), 124–135.
Abstract: Innovative behaviors such as exploiting novel food sources can grant significant fitness benefits for animals, yet little is known about the mechanisms driving such phenomena, and the role of physiology is virtually unexplored in wild species. Two hypotheses predict opposing effects of physiological state on innovation success. On one hand, poor physiological condition may promote innovations by forcing individuals with poor competitive abilities to invent alternative solutions. On the other hand, superior physiological condition may ensure greater cognitive capacity and thereby better problem-solving and learning performance. To test these hypotheses, we studied the behavior of wild-caught house sparrows (Passer domesticus) in 4 novel tasks of food acquisition, one of which was presented to the birds in repeated trials, and we investigated the relationships of individual performance with relevant physiological traits. We found that problem-solving performance across the 4 tasks was moderately consistent within individuals. Birds with lower integrated levels of corticosterone, the main avian stress hormone, solved the most difficult task faster and were more efficient learners in the repeated task than birds with higher corticosterone levels. Birds with higher concentration of total glutathione, a key antioxidant, solved 2 relatively easy tasks faster, whereas birds with fewer coccidian parasites tended to solve the difficult task more quickly. Our results, thus, indicate that aspects of physiological state influence problem-solving performance in a context-dependent manner, and these effects on problem-solving capacity, probably including cognitive abilities, are more likely to drive individual innovation success than necessity due to poor condition.
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Nakagawa, S. (2004). A farewell to Bonferroni: the problems of low statistical power and publication bias. beheco, 15(6), 1044–1045.
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Taberlet, P., Waits, L. P., & Luikart, G. (1999). Noninvasive genetic sampling: look before you leap. Trends Ecol. Evol, 14(8), 323–327.
Abstract: Noninvasive sampling allows genetic studies of free-ranging animals without the need to capture or even observe them, and thus allows questions to be addressed that cannot be answered using conventional methods. Initially, this sampling strategy promised to exploit fully the existing DNA-based technology for studies in ethology, conservation biology and population genetics. However, recent work now indicates the need for a more cautious approach, which includes quantifying the genotyping error rate. Despite this, many of the difficulties of noninvasive sampling will probably be overcome with improved methodology.
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Bruns, A., Waltert, M., & Khorozyan, I. (2020). The effectiveness of livestock protection measures against wolves (Canis lupus) and implications for their co-existence with humans. Global Ecology and Conservation, 21, e00868.
Abstract: Wolves (Canis lupus) can kill domestic livestock resulting in intense conflicts with humans. Damage to livestock should be reduced to facilitate human-wolf coexistence and ensure positive outcomes of conservation efforts. Current knowledge on the effectiveness of livestock protection measures from wolves is limited and scattered in the literature. In this study, we compiled a dataset of 30 cases describing the application of 11 measures of protecting cattle and smaller livestock against wolves, estimated their effectiveness as a relative risk of damage, and identified the best measures for damage reduction. We found that: (1) lethal control and translocation were less effective than other measures, (2) deterrents, especially fladry which is a fence with ropes marked by hanging colored flags that sway in the wind and provide a visual warning signal, were more effective than guarding dogs; (3) deterrents, fencing, calving control and herding were very effective, but the last two measures included only one case each; and (4) protection of cattle was more effective than that of small stock (sheep and goats, or sheep only) and mixed cattle and small stock. In all of these cases, the relative risk of damage was reduced by 50-100%. Considering Germany as an example of a country with a recovering wolf population and escalating human-wolf conflicts, we suggest electric fences and electrified fladry as the most promising measures, which under suitable conditions can be accompanied by well-trained livestock guarding dogs, and the temporary use of deterrents during critical periods such as calving and lambing seasons. Further research in this field is of paramount importance to efficiently mitigate human-wolf conflicts.
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