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Monitoring of reintroductions is essential, but often requires significant resources. If data are available from previous reintroductions, they can be used as priors in a Bayesian framework, potentially reducing the amount of data needed from a new reintroduced population before reasonable projections can be made. We applied this approach to the reintroduction of North Island saddlebacks ( Philesturnus rufusater) to Bushy Park, New Zealand, an 87-ha forest reserve within a fenced exclosure where exotic mammalian predators had been eradicated. We released 34 birds in June 2006, and conducted intensive monitoring of survival and fecundity until January 2010. We modeled the data in an integrated framework whereby we generated population projections concurrent with estimations of survival and fecundity parameters, meaning estimation of uncertainty was propagated into the projections. We compared projections from 1, 2, and 3 years of monitoring data, using either non-informative priors (i.e., inferences from Bushy Park only) or informative priors generated from 2 previous saddleback reintroductions where 5-8 years of data had been collected. The Bushy Park saddleback population grew rapidly over the monitoring period (approx. 80% per annum), and projections from 3 years of data with non-informative priors gave a median equilibrium breeding population of 255 with a 95% prediction interval of 122-1,238. Projections from 2 years of data gave a lesser mean equilibrium population of 93 (50-360). Projections from 1 year of data revealed uncertainty about the success of the reintroduction at this stage (8.4% of simulated populations declined), and equilibrium population size could not be projected without the density effect. Using informative priors eliminated the uncertainty about whether the population would grow, allowed equilibrium population size to be projected from 1 year of Bushy Park data, and made the projections from 2 years of data more consistent with those from the full 3-year dataset. We discuss the implications of monitoring requirements on decision making. © 2013 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Birds that counter-sing for communication and territorial maintenance need to localise the source of sound in order to promote an appropriate intraspecific response. Here, we investigate the role of harmonics in the chatter call of the North Island Saddleback (Philesturnus rufusater). We test whether the relative amplitude of harmonics serves as a distance cue, and whether a change of the harmonic composition of the chatter call has an effect on bird's response and its likely ability to estimate the distance of the signalling individual. North Island Saddlebacks exhibited stronger responses to playback songs with more relative energy within higher harmonics, suggesting that these are perceived as coming from a nearby individual. North Island Saddlebacks took longer to respond and counter-sang less to chatter calls with more relative energy in lower harmonics, suggesting that they were perceived as coming from a distant bird. We also found that North Island Saddlebacks responded differently to songs from which different harmonic frequencies were removed (muted). This study reveals the ability of the North Island Saddleback to differentiate between calls with different harmonic composition and proposes that harmonics are important as distance cues. [ABSTRACT FROM AUTHOR]

Understanding the divergence of behavioural signals in isolated populations is critical to knowing how certain barriers to gene flow can develop. For many bird species, songs are essential for conspecific recognition and mate choice. Measuring the rate of song divergence in natural populations is difficult, but translocations of endangered birds to isolated islands for conservation purposes can yield insights, as the age and source of founder populations are completely known. We found significant and rapid evolution in the structure and diversity of bird song in North Island saddlebacks, Philesturnus rufusater, in New Zealand, with two distinct lineages evolving in < 50 years. The strong environmental filters of serial translocations resulted in cultural bottlenecks that generated drift and reduced song variability within islands. This rapid divergence coupled with loss of song diversity has important implications for the behavioural evolution of this species, demonstrating previously unrecognised biological consequences of conservation management. [ABSTRACT FROM AUTHOR]

The divergence of conspecific recognition signals (CRS) among isolated populations facilitates the evolution of behavioral barriers to gene flow. The influence of CRS evolution on signal effectiveness in isolated populations can be assessed by testing the salience of changes in CRS from surviving ancestral populations but founder events are rarely detected. The population history of the North Island (NI) saddleback Philesturnus rufusater is absolutely known following conservation translocations which increased the number of populations from 1 to 15. With one exception there is no gene flow between these populations. The translocations have generated interisland divergence of male rhythmical song (MRS), a culturally transmitted CRS. We conducted an experimental test of behavioral discrimination in NI saddlebacks exposed to familiar and unfamiliar MRS and found that responses were significantly stronger for familiar MRS, consistent with a model of contemporary cultural evolution leading to discrimination between geographic song variants. Significantly, this result demonstrates the rapid tempo with which discrimination of CRS might evolve within isolated populations and supports both bottleneck and cultural mutation hypotheses in CRS evolution. The evolutionary implications of contemporary cultural evolution in the production and perception of CRS merit debate on the time frames over which conservation management is evaluated. [ABSTRACT FROM AUTHOR]

The World Conservation Union (1987) defines a translocation as a release of animals with the intention of establishing, reestablishing, or augmenting an existing population. Despite frequent use as a tool for the management of threatened and endangered wildlife, the full benefits of translocations often go unrealized. In this article, I demonstrate how translocations can achieve outputs for conservation management, conservation science, and the wider human community, using North Island (NI) Saddleback or Tieke ( Philesturnus rufusater) as an illustrative example. From a conservation management perspective, NI Saddleback have been salvaged from a relic population of less than 500 birds on 484-ha Hen Island to a metapopulation of approximately 6,000 birds on 13 offshore islands and at two mainland New Zealand sites. These translocations have reduced the risk of global extinction for this species and helped restore the ecosystems involved. All these translocations have occurred in the past 42 years from known source populations and with known numbers of birds released. The resulting replicated serial population bottlenecks provide numerous scientific opportunities for conservation and biological research. Although the first Saddleback translocations were to reserves closed to the public, subsequent translocations have been to open reserves, providing the wider human community with an opportunity to see and be actively involved in the management of a threatened endemic species. This has raised the profile of both NI Saddleback and other species and has provided wider community conservation benefits. These three outputs illustrate the value of translocations for resource management and conservation science and for increasing community interest, participation, and investment in biological conservation. [ABSTRACT FROM AUTHOR]