John G. Ewen

Reintroduction biology : integrating science and management

Contributors vii Memorium of Don Merton xi Foreword xix Preface xxiii 1. Animal Translocations: What Are They and Why DoWe Do Them? 1 Philip J. Seddon, W. Maartin Strauss and John Innes 2. A Tale of Two Islands: The Rescue and Recovery of Endemic Birds in New Zealand and Mauritius 33 Carl G. Jones and Don V. Merton 3. Selecting Suitable Habitats for Reintroductions: Variation, Change and the Role of Species Distribution Modelling 73 Patrick E. Osborne and Philip J. Seddon 4. The Theory and Practice of Catching, Holding, Moving and Releasing Animals 105 Kevin A. Parker, Molly J. Dickens, Rohan H. Clarke and Tim G. Lovegrove 5. Dispersal and Habitat Selection: Behavioural and Spatial Constraints for Animal Translocations 138 Pascaline Le Gouar, Jean-Baptiste Mihoub and Franc,ois Sarrazin 6. Modelling Reintroduced Populations: The State of the Art and Future Directions 165 Doug P. Armstrong and Michelle H. Reynolds 7. Monitoring for Reintroductions 223 James D. Nichols and Doug P. Armstrong 8. Adaptive Management of Reintroduction 256 Michael A. McCarthy, Doug P. Armstrong and Michael C. Runge 9. Empirical Consideration of Parasites and Health in Reintroduction 290 John G. Ewen, Karina Acevedo-Whitehouse, Maurice R. Alley, Claudia Carraro, Anthony W. Sainsbury, Kirsty Swinnerton and Rosie Woodroffe 10. Methods of Disease Risk Analysis for Reintroduction Programmes 336 Anthony W. Sainsbury, Doug P. Armstrong and John G. Ewen 11. The Genetics of Reintroductions: Inbreeding and Genetic Drift 360 Lukas F. Keller, Iris Biebach, Steven R. Ewing and Paquita E.A. Hoeck 12. Genetic Consequences of Reintroductions and Insights from Population History 395 Jim J. Groombridge, Claire Raisin, Rachel Bristol and David S. Richardson 13. Managing Genetic Issues in Reintroduction Biology 441 Ian G. Jamieson and Robert C. Lacy 14. Summary 476 Philip J. Seddon, Doug P. Armstrong, Kevin A. Parker and John G. Ewen Index 483

Eggshell colour does not predict measures of maternal investment in eggs of Turdus thrushes.

The striking diversity of avian eggshell colour has long fascinated biologists. Recently, it has been proposed that the blue-green colour of some eggs may function as a post-mating sexually selected signal of female phenotypic quality to their mates to induce higher allocation of paternal care. It has been suggested that maternally deposited yolk carotenoids may be the specific aspect of reproductive quality that the female is signalling via eggshell colour. We use the known properties of the thrush visual system (Turdus sp.) to calculate photon capture for the four single cone photoreceptors, and the principal member of the double cone class for eggs in clutches of two introduced European thrush species (Turdus merula and Turdus philomelos) in New Zealand. We show that differences in the avian-perceived colours of individual eggs are not consistently correlated with different measures of maternal investment in the egg. Given the growing extent of the knowledge between maternal quality, parental investment and eggshell pigmentation across avian taxa, we encourage the use of avian perceptual modelling for testing alternative non-signalling explanations for the structural and physiological basis of these relationships.

Strategic monitoring of reintroductions in ecological restoration programmes

Abstract It is well recognized that reintroductions have previously suffered from insufficient monitoring, and as a result reintroduction protocols and guidelines now have stringent monitoring requirements. It is important, however, that monitoring is done strategically. To be cost efficient, monitoring must be designed to address key questions relevant to reintroduction success and must be allocated to reintroductions where monitoring will have the greatest value. While the traditional aim of reintroductions was to recover endangered species, there is now a much greater emphasis on reintroduction as part of ecological restoration programmes. This often means that whole suites of species are re-introduced, including common as well as endangered species. We recommend the following approach for strategically monitoring reintroductions in restoration programmes. First, monitoring should be allocated not just to the rarest species, but to focal species chosen based on restoration objectives. Second, monitoring should primarily aim to assess the suitability of the habitat for supporting the species in the long-term, rather than the short-term effects of different release strategies (e.g., soft versus hard release). Third, an experimental approach should be used where possible to test the extent to which habitat factors such as food and predators are limiting population viability. We provide examples from our research on 2 species of New Zealand forest birds being reintroduced as part of ecological restoration programmes.

Reintroducing resurrected species: selecting DeExtinction candidates

Technological advances have raised the controversial prospect of resurrecting extinct species. Species DeExtinction should involve more than the production of biological orphans to be scrutinized in the laboratory or zoo. If DeExtinction is to realize its stated goals of deep ecological enrichment, then resurrected animals must be translocated (i.e., released within suitable habitat). Therefore, DeExtinction is a conservation translocation issue and the selection of potential DeExtinction candidates must consider the feasibility and risks associated with reintroduction. The International Union for the Conservation of Nature (IUCN) Guidelines on Reintroductions and Other Conservation Translocations provide a framework for DeExtinction candidate selection. We translate these Guidelines into ten questions to be addressed early on in the selection process to eliminate unsuitable reintroduction candidates. We apply these questions to the thylacine, Yangtze River Dolphin, and Xerces blue butterfly.

Sensitive males: inbreeding depression in an endangered bird

Attempts to conserve threatened species by establishing new populations via reintroduction are controversial. Theory predicts that genetic bottlenecks result in increased mating between relatives and inbreeding depression. However, few studies of wild sourced reintroductions have carefully examined these genetic consequences. Our study assesses inbreeding and inbreeding depression in a free-living reintroduced population of an endangered New Zealand bird, the hihi (Notiomystis cincta). Using molecular sexing and marker-based inbreeding coefficients estimated from 19 autosomal microsatellite loci, we show that (i) inbreeding depresses offspring survival, (ii) male embryos are more inbred on average than female embryos, (iii) the effect of inbreeding depression is male-biased and (iv) this population has a substantial genetic load. Male susceptibility to inbreeding during embryo and nestling development may be due to size dimorphism, resulting in faster growth rates and more stressful development for male embryos and nestlings compared with females. This work highlights the effects of inbreeding at early life-history stages and the repercussions for the long-term population viability of threatened species.

Social and sexual monogamy in translocated New Zealand robin populations detected using minisatellite DNA

MARTIN, T. E., AND J. J. RoPER. 1988. Nest predation and nest-site selection of a western population of the Hermit Thrush. Condor 90:51-57. MARZLUFF, J. M., R. B. BOONE, AND G. W. Cox. 1994. Historical changes in populations and perceptions of native pest bird species in the West. Pages 202-220 in A century of avifaunal change in western North America (J. R. Jehl, Jr. and N. K. Johnson, Eds.). Studies in Avian Biology No. 15. MOSHER, J. A., K. TITUS, AND M. FULLER. 1986. Developing a practical model to predict nesting habitat of woodland hawks. Pages 31-35 in Wildlife 2000: Modeling habitat relationships of terrestrial vertebrates (J. Verner, M. L. Morrison, and C.J. Ralph, Eds.). University of Wisconsin Press, Madison. NOON, B. R. 1981. Techniques for sampling avian habitats. Pages 42-52 in The use of multivariate statistics in studies of wildlife habitat (D. E. Capen, Ed.). General Technical Report RM-87, U. S. Forest Service, Fort Collins, Colorado. ORLANs, G., AND F. KUHLMAN. 1956. Red-tailed Hawks and Horned Owl populations in Wisconsin. Condor 58:371-385. PARKER, J. W. 1972. A mirror pole device for examining high nests. Bird-Banding 43:216-218. PETIT, L. J., AND D. R. PETIT. 1996. Factors governing habitat selection by Prothonotary Warblers: Field tests of the Fretwell-Lucas models. Ecological Monographs 66:367-387. POSTUPALSKY, S. 1974. Raptor reproductive success: Some problems with methods, criteria, and terminology. Pages 21-31 in Management of raptors (F. N. Hamerstrom, Jr., B. E. Harrell, and R. R. Olendorff, Eds.). Raptor Research Report No. 2. Raptor Research Foundation, Inc. Vermillion, South Dakota. RATCLIFFE, D. A. 1962. Breeding density in the Peregrine (Falco peregrinus) and Raven (Corvus corax). Ibis 104:13-39. SEAMANS, M. E., AND R. J. GuritRREz. 1995. Breeding habitat of the Mexican Spotted Owl in the Tularosa Mountains, New Mexico. Condor 97:944: 952. SKARPHtDINSSON, K. H., 0. K NIELSEN, S. TH6RISSON, S. THORSTENSEN, AND S. A. TEMPLE. 1990. Breeding biology, movements, and persecution of Ravens in Iceland. Acta Naturalia Islandica 33:1-45. SMITH, R. N. 1994. Factors affecting Red-tailed Hawk reproductive success in Grand Teton National Park, Wyoming. M. S. thesis, University of Wyoming, Laramie. Trrus, K., J. A. MOSHER, AND B. K. WILLIAMS. 1984. Chance-corrected classification for use in discriminant analysis: Ecological applications. American Midland Naturalist 107:1-7. WHITE, C. M., AND T. J. CADE. 1971. Cliff-nesting raptors and Ravens along the Colville River in Arctic Alaska. Living Bird 10:107-149. WHITE, C. M., AND M. TANNER-WHITE. 1988. Use of interstate highway overpasses and billboards for nesting by the Common Raven (Corvus corax). Great Basin Naturalist 48:64-67.

High genetic diversity in the remnant island population of hihi and the genetic consequences of re-introduction

The maintenance of genetic diversity is thought to be fundamental for the conservation of threatened species. It is therefore important to understand how genetic diversity is affected by the re‐introduction of threatened species. We use establishment history and genetic data from the remnant and re‐introduced populations of a New Zealand endemic bird, the hihi Notiomystis cincta, to understand genetic diversity loss and quantify the genetic effects of re‐introduction. Our data do not support any recent bottleneck events in the remnant population. Furthermore, all genetic diversity measures indicate the remnant hihi population has retained high levels of genetic diversity relative to other New Zealand avifauna with similar histories of decline. Genetic diversity (NA, alleles per locus, allelic richness, FIS and HS) did not significantly decrease in new hihi populations founded through re‐introduction when compared to their source populations, except in the Kapiti Island population (allelic richness and HS) which had very slow post‐re‐introduction population growth. The Ne/Nc ratio in the remnant population was high, but decreased in first‐level re‐introductions, which together with significant genetic differentiation between populations (FST & Fisher’s exact tests) suggest that extant populations are diverging as a result of founder effects and drift. Importantly, simulations of future allele loss predict that the number of alleles lost will be higher in populations with a slow population growth, fewer founding individuals and with nonrandom mating. Interestingly, this species has very high levels of extra‐pair paternity which may reduce reproductive variance by allowing social and floater males to reproduce a life history trait that together with a large remnant population size may help maintain higher levels of genetic diversity than expected.

Variability in Avian Eggshell Colour: A Comparative Study of Museum Eggshells

Background The exceptional diversity of coloration found in avian eggshells has long fascinated biologists and inspired a broad range of adaptive hypotheses to explain its evolution. Three main impediments to understanding the variability of eggshell appearance are: (1) the reliable quantification of the variation in eggshell colours; (2) its perception by birds themselves, and (3) its relation to avian phylogeny. Here we use an extensive museum collection to address these problems directly, and to test how diversity in eggshell coloration is distributed among different phylogenetic levels of the class Aves. Methodology and Results Spectrophotometric data on eggshell coloration were collected from a taxonomically representative sample of 251 bird species to determine the change in reflectance across different wavelengths and the taxonomic level where the variation resides. As many hypotheses for the evolution of eggshell coloration assume that egg colours provide a communication signal for an avian receiver, we also modelled reflectance spectra of shell coloration for the avian visual system. We found that a majority of species have eggs with similar background colour (long wavelengths) but that striking differences are just as likely to occur between congeners as between members of different families. The region of greatest variability in eggshell colour among closely related species coincided with the medium-wavelength sensitive region around 500 nm. Conclusions The majority of bird species share similar background eggshell colours, while the greatest variability among species aligns with differences along a red-brown to blue axis that most likely corresponds with variation in the presence and concentration of two tetrapyrrole pigments responsible for eggshell coloration. Additionally, our results confirm previous findings of temporal changes in museum collections, and this will be of particular concern for studies testing intraspecific hypotheses relating temporal patterns to adaptation of eggshell colour. We suggest that future studies investigating the phylogenetic association between the composition and concentration of eggshell pigments, and between the evolutionary drivers and functional impacts of eggshell colour variability will be most rewarding.

Maternally invested carotenoids compensate costly ectoparasitism in the hihi

Dietary ingested carotenoid biomolecules have been linked to both improved health and immunity in nestling birds. Here, we test whether maternally invested egg carotenoids can offset the cost of parasitism in developing nestling hihi (Notiomystis cincta) from the bloodsucking mite (Ornithonyssus bursa). Our results reveal clear negative effects of parasitism on nestlings, and that maternally derived carotenoids compensate this cost, resulting in growth parameters and ultimate mass achieved being similar to nonparasitized young. Our results offer an unique example of a direct positive relationship between enhanced maternal investment of carotenoids and an ability to cope with a specific and costly parasite in young birds. As O. bursa infestations reduce population viability in hihi, our findings also highlight the importance of key nutritional resources for endangered bird populations to better cope with common parasite infestations.

Sense and sensitivity: responsiveness to offspring signals varies with the parents' potential to breed again

How sensitive should parents be to the demands of their young? Offspring are under selection to seek more investment than is optimal for parents to supply, which makes parents vulnerable to losing future fitness by responding to manipulative displays. Yet, parents cannot afford to ignore begging and risk allocating resources inefficiently. Here, we show that parents may solve this problem by adjusting their sensitivity to begging behaviour in relation to their own likelihood of breeding again, a factor largely neglected in previous analyses of parent–offspring interactions. In two carotenoid-supplementation experiments on a New Zealand passerine, the hihi Notiomystis cincta, we supplemented adults to enhance their propensity to breed again, and supplemented entire broods to increase their mouth colour, thus enhancing their solicitation display. We found that adults that attempted two breeding attempts a season were largely insensitive to the experimentally carotenoid-rich gapes of their brood, whereas those that bred just once responded by increasing their rate of provisioning at the nest. Our results show that parents can strategically vary their sensitivity to begging in relation to their future reproductive potential. By restricting opportunities for offspring to influence provisioning decisions, parents greatly limit the potential for offspring to win parent–offspring conflict.