Does Natural Visual Camouflage Reduce Turtle Nest Predation?

Voves, Kameron C.; Mitchell, Timothy S.; Janzen, Fredric J.

doi:10.1674/0003-0031-176.1.166

Cited by 10 publications

(11 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Do reptiles discriminate among substrate types when selecting a nest? Different substrate types might appear, smell, or feel differently to predators, which could influence predation rates (Oddie et al 2015;Voves et al 2016), and thus, exert direct fitness consequences of nest location for offspring. Perhaps more indirectly for offspring fitness, ease of nest construction, which also affects subsequent hatchling emergence, might vary between substrate types and thus influence nest-site choice (Mortimer 1990).…”

Section: Discussionmentioning

confidence: 99%

Substrate Influences Turtle Nest Temperature, Incubation Period, and Offspring Sex Ratio in the Field

Mitchell

Janzen

2019

Herpetologica

Self Cite

View full text Add to dashboard Cite

Temperature-dependent sex determination, where egg incubation temperature irreversibly determines offspring sex, is a common sex-determining mechanism in reptiles. Weather is the primary determinant of temperature in reptile nests, yet the effects of weather are mediated through the nest microhabitat selected by the mother (e.g., overstory canopy cover). One potentially important aspect of the nest microhabitat is the physical substrate used for nesting. However, the influence of substrate type on nest temperature and offspring sex determination has never been experimentally assessed in the field. We incubated eggs of Painted Turtles (Chrysemys picta) in three substrate types similar to those commonly selected for nesting within our study population. Within a single study site, we constructed pits, which we refilled with loam, sand, or gravel. Then, we created artificial nests in each substrate type, and randomly assigned eggs to a substrate treatment. Substrate type influenced nest temperature and soil moisture, and affected incubation duration, but no other phenotype measured beyond offspring sex ratios. The cooler loam yielded the most male-biased outcome. This finding illustrates the potential importance of nesting substrate as a component of nest-site choice and as a factor in modeling future nest temperature scenarios. CommentsThis is a manuscript of an article published as Mitchell, Timothy S., and Fredric J. Janzen. "Substrate Influences Turtle Nest Temperature, Incubation Period, and Offspring Sex Ratio in the Field." Herpetologica 75, no. 1 (2019): 57-62.

show abstract

Section: Discussionmentioning

confidence: 99%

Substrate Influences Turtle Nest Temperature, Incubation Period, and Offspring Sex Ratio in the Field

Mitchell

Janzen

2019

Herpetologica

Self Cite

View full text Add to dashboard Cite

show abstract

“…On the other hand, the visual attraction related with the soil revolved should also be considered (Fagundes et al, 2010). Artificial nests with visual soil disturbance are more likely to be depredated than artificial nests lacking soil disturbance (Strickland et al, 2010;Voves et al, 2016). The absence of olfactory traces, such as the odor of eggs and the metabolites produced by the eggs inside the nests did not interfere in the probability to attract predators.…”

mentioning

confidence: 96%

“…The location of chelonian nests by predators might be facilitated by sighting females during the spawning or by olfactory traces associated with females' secretions during the spawning, smell of eggs and/or soil revolved in nest construction (Wilhoft et al, 1979). According to Moll and Legler (1971), the location of nests of Trachemys scripta Wied-Neuwied 1839 by lizards and armadillos occurred through the detection of odor of females' urine, but the visual vestiges could be act in the successful nest predation.…”

mentioning

confidence: 99%

“…Turtle nests are highly detectable by predators and mothers have little ability to influence predation risk of their nests (Voves et al, 2016). Probably, predators attack nests when they find any olfactory or visual cues from a possible nest.…”

mentioning

confidence: 99%

“…Olfactory cues thus could be important in locating nests, especially as a result from the female voiding her bladder prior to digging (Burke et al, 2005;Oddie et al, 2015). However, turtle-related olfactory cues are not necessary in nest predation (Wilhoft et al, 1979;Burke et al, 2005;Strickland et al, 2010;Bernstein et al, 2015;Geller, 2015). Other cues could be soil disturbance-related which are inherent in the construction of artificial nests and produces both visual and olfactory signals that have led to difficulties in resolving which are used as nest location cues (Geller, 2015).…”

mentioning

confidence: 99%

See 2 more Smart Citations

Is the presence of eggs a relevant cue for predators of freshwater chelonian nests?

Perazzo

Garcez

Trindade

et al. 2018

Neotropical Biology and Conservation

View full text Add to dashboard Cite

Predation is considered a game between two players-predator and prey-where such pressure might affect the interactions, acting on prey and predator distribution and abundance. We evaluate whether the predation level in chelonian nests varies according to the presence of eggs in nests. Our hypothesis is that owing to the clues (visual and olfactory) of upturned soil left in newly constructed nests, predators attack nests regardless of the presence of eggs on nests. We constructed artificial nests organized in two treatments (15 with eggs, and 15 without eggs) in ESEC Taim, southern Brazil, and checked the nests during two consecutive days. We identified the possible predators through photographic traps installed near the nests, associated with the identification of footprints on disturbed nests. We verified high predation rates in both nests, which corroborate our hypothesis. We identified two canids (Cerdocyon thous and Lycalopex gymnocercus) as predators around the nests. Our results suggest that turtle nests are highly detectable by predators, and the location cues used by pampa fox to find newly constructed nests are related to soil disturbance and not to egg presence on nests.

show abstract

Risk-sensitive maternal investment: an evaluation of parent–offspring conflict over nest site choice in the wild

Delaney

Janzen

2020

Animal Behaviour

Self Cite

View full text Add to dashboard Cite

Does Natural Visual Camouflage Reduce Turtle Nest Predation?

Cited by 10 publications

References 25 publications

Substrate Influences Turtle Nest Temperature, Incubation Period, and Offspring Sex Ratio in the Field

Substrate Influences Turtle Nest Temperature, Incubation Period, and Offspring Sex Ratio in the Field

Is the presence of eggs a relevant cue for predators of freshwater chelonian nests?

Risk-sensitive maternal investment: an evaluation of parent–offspring conflict over nest site choice in the wild

Contact Info

Product

Resources

About