Conditional female strategies influence hatching success in a communally nesting iguana
Abstract The decision of females to nest communally has important consequences for reproductive success. While often associated with reduced energetic expenditure, conspecific aggregations also expose females and offspring to conspecific aggression, exploitation, and infanticide. Intrasexual competi...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Wiley
2020-04-01
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| Series: | Ecology and Evolution |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/ece3.6139 |
| _version_ | 1818459258873708544 |
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| author | Jeanette B. Moss Glenn P. Gerber Tanja Laaser Matthias Goetz TayVanis Oyog Mark E. Welch |
| author_facet | Jeanette B. Moss Glenn P. Gerber Tanja Laaser Matthias Goetz TayVanis Oyog Mark E. Welch |
| author_sort | Jeanette B. Moss |
| collection | DOAJ |
| description | Abstract The decision of females to nest communally has important consequences for reproductive success. While often associated with reduced energetic expenditure, conspecific aggregations also expose females and offspring to conspecific aggression, exploitation, and infanticide. Intrasexual competition pressures are expected to favor the evolution of conditional strategies, which could be based on simple decision rules (i.e., availability of nesting sites and synchronicity with conspecifics) or on a focal individual's condition or status (i.e., body size). Oviparous reptiles that reproduce seasonally and provide limited to no postnatal care provide ideal systems for disentangling social factors that influence different female reproductive tactics from those present in offspring‐rearing environments. In this study, we investigated whether nesting strategies in a West Indian rock iguana, Cyclura nubila caymanensis, vary conditionally with reproductive timing or body size, and evaluated consequences for nesting success. Nesting surveys were conducted on Little Cayman, Cayman Islands, British West Indies for four consecutive years. Use of high‐density nesting sites was increasingly favored up to seasonal nesting activity peaks, after which nesting was generally restricted to low‐density nesting areas. Although larger females were not more likely than smaller females to nest in high‐density areas, larger females nested earlier and gained access to priority oviposition sites. Smaller females constructed nests later in the season, apparently foregoing investment in extended nest defense. Late‐season nests were also constructed at shallower depths and exhibited shorter incubation periods. While nest depth and incubation length had significant effects on reproductive outcomes, so did local nest densities. Higher densities were associated with significant declines in hatching success, with up to 20% of egg‐filled nests experiencing later intrusion by a conspecific. Despite these risks, nests in high‐density areas were significantly more successful than elsewhere due to the benefits of greater chamber depths and longer incubation times. These results imply that communal nest sites convey honest signals of habitat quality, but that gaining and defending priority oviposition sites requires competitive ability. |
| first_indexed | 2024-12-14T23:11:30Z |
| format | Article |
| id | doaj.art-67bceafd84cd435eb2eeda4c589239b4 |
| institution | Directory Open Access Journal |
| issn | 2045-7758 |
| language | English |
| last_indexed | 2024-12-14T23:11:30Z |
| publishDate | 2020-04-01 |
| publisher | Wiley |
| record_format | Article |
| series | Ecology and Evolution |
| spelling | doaj.art-67bceafd84cd435eb2eeda4c589239b42022-12-21T22:44:11ZengWileyEcology and Evolution2045-77582020-04-011073424343810.1002/ece3.6139Conditional female strategies influence hatching success in a communally nesting iguanaJeanette B. Moss0Glenn P. Gerber1Tanja Laaser2Matthias Goetz3TayVanis Oyog4Mark E. Welch5Biological Sciences Department Mississippi State University Mississippi State MS USAInstitute for Conservation Research San Diego Zoo Global Escondido CA USACayman Islands Department of Environment George Town Cayman IslandsDepartment of Herpetology Durrell Wildlife Conservation Trust Jersey UKCayman Islands Department of Environment George Town Cayman IslandsBiological Sciences Department Mississippi State University Mississippi State MS USAAbstract The decision of females to nest communally has important consequences for reproductive success. While often associated with reduced energetic expenditure, conspecific aggregations also expose females and offspring to conspecific aggression, exploitation, and infanticide. Intrasexual competition pressures are expected to favor the evolution of conditional strategies, which could be based on simple decision rules (i.e., availability of nesting sites and synchronicity with conspecifics) or on a focal individual's condition or status (i.e., body size). Oviparous reptiles that reproduce seasonally and provide limited to no postnatal care provide ideal systems for disentangling social factors that influence different female reproductive tactics from those present in offspring‐rearing environments. In this study, we investigated whether nesting strategies in a West Indian rock iguana, Cyclura nubila caymanensis, vary conditionally with reproductive timing or body size, and evaluated consequences for nesting success. Nesting surveys were conducted on Little Cayman, Cayman Islands, British West Indies for four consecutive years. Use of high‐density nesting sites was increasingly favored up to seasonal nesting activity peaks, after which nesting was generally restricted to low‐density nesting areas. Although larger females were not more likely than smaller females to nest in high‐density areas, larger females nested earlier and gained access to priority oviposition sites. Smaller females constructed nests later in the season, apparently foregoing investment in extended nest defense. Late‐season nests were also constructed at shallower depths and exhibited shorter incubation periods. While nest depth and incubation length had significant effects on reproductive outcomes, so did local nest densities. Higher densities were associated with significant declines in hatching success, with up to 20% of egg‐filled nests experiencing later intrusion by a conspecific. Despite these risks, nests in high‐density areas were significantly more successful than elsewhere due to the benefits of greater chamber depths and longer incubation times. These results imply that communal nest sites convey honest signals of habitat quality, but that gaining and defending priority oviposition sites requires competitive ability.https://doi.org/10.1002/ece3.6139aggregative ovipositionearly incubation environmentegg chamberreproductive tacticssquamate reptileWest Indian rock iguana |
| spellingShingle | Jeanette B. Moss Glenn P. Gerber Tanja Laaser Matthias Goetz TayVanis Oyog Mark E. Welch Conditional female strategies influence hatching success in a communally nesting iguana Ecology and Evolution aggregative oviposition early incubation environment egg chamber reproductive tactics squamate reptile West Indian rock iguana |
| title | Conditional female strategies influence hatching success in a communally nesting iguana |
| title_full | Conditional female strategies influence hatching success in a communally nesting iguana |
| title_fullStr | Conditional female strategies influence hatching success in a communally nesting iguana |
| title_full_unstemmed | Conditional female strategies influence hatching success in a communally nesting iguana |
| title_short | Conditional female strategies influence hatching success in a communally nesting iguana |
| title_sort | conditional female strategies influence hatching success in a communally nesting iguana |
| topic | aggregative oviposition early incubation environment egg chamber reproductive tactics squamate reptile West Indian rock iguana |
| url | https://doi.org/10.1002/ece3.6139 |
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