Predicting species interactions from edge responses: mongoose predation on hawksbill sea turtle nests in fragmented beach habitat

Because species respond differently to habitat boundaries and spatial overlap affects encounter rates, edge responses should be strong determinants of spatial patterns of species interactions. In the Caribbean, mongooses ( Herpestes javanicus ) prey on hawksbill sea turtle ( Eretmochelys imbricata ) eggs. Turtles nest in both open sand and vegetation patches, with a peak in nest abundance near the boundary between the two microhabitats; mongooses rarely leave vegetation. Using both artificial nests and hawksbill nesting data, we examined how the edge responses of these species predict the spatial patterns of nest mortality. Predation risk was strongly related to mongoose abundance but was not affected by nest density or habitat type. The product of predator and prey edge response functions accurately described the observed pattern of total prey mortality. Hawksbill preference for vegetation edge becomes an ecological trap in the presence of mongooses. This is the first study to predict patterns of predation directly from continuous edge response functions of interacting species, establishing a link between models of edge response and species interactions.

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Effect of Truncation of Line-Spread and Edge-Response Functions on the Computed Optical Transfer Function

Journal of the Optical Society of America ◽

10.1364/josa.59.001309 ◽

1969 ◽

Vol 59 (10) ◽

pp. 1309 ◽

Cited By ~ 7

Author(s):

M. E. Rabedeau

Keyword(s):

Transfer Function ◽

Optical Transfer Function ◽

Response Functions ◽

Optical Transfer ◽

Edge Response ◽

Line Spread

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The Occurence of Ecological Traps in Bird Populations: Is our Knowledge Sufficient? A Review

Journal of Landscape Ecology ◽

10.2478/v10285-012-0058-4 ◽

2012 ◽

Vol 5 (3) ◽

pp. 36-56 ◽

Cited By ~ 4

Author(s):

Petr Suvorov ◽

Jana Svobodová

Keyword(s):

Exotic Species ◽

Species Conservation ◽

Habitat Type ◽

Bird Species ◽

Ecological Trap ◽

Native Communities ◽

Bird Populations ◽

Suburban Areas ◽

Arable Fields ◽

Insufficient Time

ABSTRACT Anthropogenic changes in a landscape create new cues for birds, which must permanently adapt to these. If landscape changes occur too quickly, individuals have insufficient time to develop adequate reactions. They may, therefore, preferentially nest in low-quality habitats, which can lead to diminished nesting success and to reduction of their population size. This is usually termed the ecological trap hypothesis. We reviewed 38 studies investigating this phenomenon and analysed whether relationships exist between ecological trap occurrence and geographical region, habitat type, and/or life strategies of bird species. Ecological traps were most often associated with the presence of exotic species. Exotic species can modify environmental conditions in ways to which native communities are not adapted. They have been mainly detected in open habitats. Such open habitats as arable fields and meadows are under greater human pressure, and rapid changes probably occur there more frequently. Although more studies from North America were investigated, the hypothesis was supported more frequently in European studies. This is possibly due to higher human population density and, hence, more frequent habitat changes. Our results show that an ecological trap is not likely associated with migration. Ground nests suffered fewer consequences of such traps than did other nest types. Although the implications of the ecological trap hypothesis in species conservation are undisputable, a more detailed approach is still needed. For instance, some habitat types, such as suburban areas, have been neglected in the context of ecological traps, as has been the phenomenon’s appearance in pristine habitats.

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Determination and Maternal Transfer of Heavy Metals (Cd, Cu, Zn, Pb and Hg) in the Hawksbill Sea Turtle (Eretmochelys imbricata) from a Nesting Colony of Qeshm Island, Iran

Bulletin of Environmental Contamination and Toxicology ◽

10.1007/s00128-014-1244-3 ◽

2014 ◽

Vol 92 (6) ◽

pp. 667-673 ◽

Cited By ~ 22

Author(s):

Maryam Ehsanpour ◽

Majid Afkhami ◽

Reza Khoshnood ◽

Kimberly J. Reich

Keyword(s):

Heavy Metals ◽

Sea Turtle ◽

Maternal Transfer ◽

Qeshm Island ◽

Eretmochelys Imbricata

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Association between nighttime artificial light pollution and sea turtle nest density along Florida coast: A geospatial study using VIIRS remote sensing data

Environmental Pollution ◽

10.1016/j.envpol.2018.04.021 ◽

2018 ◽

Vol 239 ◽

pp. 30-42 ◽

Cited By ~ 20

Author(s):

Zhiyong Hu ◽

Hongda Hu ◽

Yuxia Huang

Keyword(s):

Remote Sensing ◽

Remote Sensing Data ◽

Sea Turtle ◽

Light Pollution ◽

Nest Density ◽

Artificial Light ◽

Sensing Data

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Is it safe to nest near bold neighbours? Spatial patterns in predation risk associated with the density of American Golden-Plover nest

10.7287/peerj.preprints.1929v1 ◽

2016 ◽

Author(s):

Marie-Andrée Giroux ◽

Myriam Trottier-Paquet ◽

Joël Bêty ◽

Vincent Lamarre ◽

Nicolas Lecomte

Keyword(s):

Predation Risk ◽

Spatial Patterns ◽

Bird Species ◽

Artificial Nests ◽

Species Of Conservation Concern ◽

Composition And Structure ◽

Negative Effect ◽

Conservation Concern ◽

Golden Plover ◽

Mobbing Behaviour

Predation is one of the main factors explaining nesting mortality in most bird species. Birds can avoid nest predation or reduce predation pressure by breeding at higher latitude, showing anti-predator behaviour, and nesting in association with protective species. Plovers actively defend their territory by displaying early warning and aggressive/mobbing behaviour, potentially benefiting the neighbouring nests by decreasing their predation risk. To test for the existence of such a protective effect, we studied the influence of proximity to plover nests on predation risk of artificial nests on Igloolik Island (Nunavut, Canada) in July 2014. We predicted that the predation risk of artificial nests increases and decreases with the distance to and the density of plover nests, respectively. We monitored 18 plover nests and set 35 artificial nests at 30, 50, 100, 200 and 500 m from seven of those plover nests. Surprisingly, we showed that predation risk of artificial nests increases with the density of active plover nests. We also found a significant negative effect of the distance to the nearest active protector nest on predation risk of artificial nests. Understanding how the composition and structure of shorebird communities generate spatial patterns in predation risks represent a key step to better understand the importance of these species of conservation concern in tundra food webs.

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Location, location, location: finding a suitable home among the noise

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2012.0697 ◽

2012 ◽

Vol 279 (1742) ◽

pp. 3622-3631 ◽

Cited By ~ 53

Author(s):

Jenni A. Stanley ◽

Craig A. Radford ◽

Andrew G. Jeffs

Keyword(s):

Spatial Patterns ◽

Habitat Type ◽

Underwater Sound ◽

Crab Species ◽

Habitat Types ◽

Location Finding ◽

Settlement And Metamorphosis

While sound is a useful cue for guiding the onshore orientation of larvae because it travels long distances underwater, it also has the potential to convey valuable information about the quality and type of the habitat at the source. Here, we provide, to our knowledge, the first evidence that settlement-stage coastal crab species can interpret and show a strong settlement and metamorphosis response to habitat-related differences in natural underwater sound. Laboratory- and field-based experiments demonstrated that time to metamorphosis in the settlement-stage larvae of common coastal crab species varied in response to different underwater sound signatures produced by different habitat types. The megalopae of five species of both temperate and tropical crabs showed a significant decrease in time to metamorphosis, when exposed to sound from their optimal settlement habitat type compared with other habitat types. These results indicate that sounds emanating from specific underwater habitats may play a major role in determining spatial patterns of recruitment in coastal crab species.

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