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Climate change is causing spatio-temporal shifts in environmental conditions, and species that are not able to track suitable environments may face increased risks of extinction. Assisted colonization, a form of translocation, has been proposed as a tool to help species survive the impacts of climate change. Unfortunately, translocations generally have a low success rate, a well-documented fact that is not considered in most of the recent literature on assisted colonization. One of the main impediments to translocation success is inadequate planning. In this review, we argue that by using well-known analytical tools such as species distribution models and population dynamics modelling we can maximize the success of assisted colonization. In particular, we present guidelines as to which questions should be investigated when planning assisted colonization and suggest methods for answering them. Finally, we also highlight further implementation and research issues that remain to be solved for assisted colonizations to be efficient climate change adaptation tools. [ABSTRACT FROM AUTHOR]

Translocations are commonly used conservation actions that aim at establishing new, self-sustaining populations of threatened species. However, many translocated populations are not self-sustaining but managed through supplemental feeding from the onset. Often, the decision to start managing is ad hoc, but managers will eventually have to make decisions for the future, for example, stop intervening, continue as it is or change the quantity of food provided. Such a decision requires managers to quantify the importance of supplemental feeding in determining the performance and population dynamics of translocated populations, information that is rarely available in the published literature. Using the hihi as a case study, we examined the importance of supplemental feeding for the viability of a translocated population in New Zealand. We found that supplemental feeding positively affected the survival and abundance of translocated adult hihi but also found evidence of negative density dependence on recruitment. We present two stochastic population models that project the hihi population under different management scenarios, quantitatively assessing the impact supplemental feeding has had on the population. Our results illustrate how important long-term targeted monitoring is for robust decision making about adaptive management. [ABSTRACT FROM AUTHOR]

A case study modelling approach was used to examine changes to a dairy farm in south-west Victoria to maintain or increase profit in the future 5-10 years in the face of some 'cost-price squeeze', emphasising impacts on both returns and risk. Five changes to the status quo system were analysed. Each involved increasing pasture consumption on the milking area and non-milking leased area (where appropriate). The five changes were: (1) reducing leased non-milking area by 100 ha; (2) converting 60 ha of non-milking leased area to milking area, reducing leased non-milking area by 100 ha and reducing stocking rate on the milking area; (3) converting 187 ha of leased non-milking area to milking area, increasing herd size to 800 cows and reducing stocking rate on the milking area; (4) discarding all leased area, reducing herd size to 370 cows and reducing stocking rate; and (5) converting 127 ha of non-milking leased area to milking area, discarding all other lease arrangements and reducing stocking rate. Mean ± standard deviation of nominal owner's equity at the end of Year 10 was $2.59M ± $1.33M, $5.42M ± $1.26M, $5.76M ± $1.21M, $7.47M ± $1.64M, $6.01M ± $0.78M and $6.10M ± $1.19M for the status quo and development options 1-5, respectively. For most but not all of the development options, the risk associated with the profit, cash and equity as measured by a range of indicators improved markedly over the performance of the farm system under the status quo. Both substantial increases and decreases in herd size were attractive. Irrespective of the direction of change in herd size, the most profitable options involved reducing stocking rate per ha and reducing purchased supplementary feed compared with the status quo. Significantly, changing to increase productivity greatly reduced the risk of having less equity at the end of Year 10 than the starting equity. Optimising the amount of home-grown grazed feed, and using purchased supplements efficiently are important, particularly if the milk being sold is subject to export market prices and variation. The most appropriate changes to dairy farm businesses in response to changes in the operating environment will vary from farm to farm - but maintaining the status quo in the face of change is not an option that meets farm family goals. Declining terms of trade is the reality for farmers. The 'whole farm systems approach' can be used to compare the cash, profit, wealth and risk impacts of alternative futures for a farm business. Options to increase profit may involve intensifying or extensifying, and/or reducing or increasing the size of the venture. This approach allows the exploration of relevant questions for a farm business. [ABSTRACT FROM AUTHOR]

The importance of accounting for temporal variation in vital rates when modelling population dynamics is well recognized. However, long‐term (usually >5 years) datasets are needed to estimate this variation. Consequently, models for newly monitored populations typically assume no temporal variation or use default values provided in software programmes, both of which can give misleading inferences about population dynamics. The goal of this study is to improve estimation of dynamics in the initial years of conservation programmes by incorporating data‐based estimates of temporal variation from other populations with longer‐term data available. We show how data‐derived priors can be generated using estimates of temporal variation in vital rates from other populations, providing information about expected variation until sufficient population‐specific data are available. We specifically evaluated whether data‐derived priors improved our ability to estimate temporal variation for a reintroduced population monitored for 3 years postrelease. We first predicted population growth and probability of extinction assuming no temporal variation in vital rates, then compared projections to those obtained when temporal variation was estimated with uniform priors or with the data‐derived priors. Both types of priors were constrained to plausible ranges, and we also assessed sensitivity of model outputs to widening those ranges. Median projected population size was similar under all three models, but extinction probability was higher with inclusion of temporal variability, reiterating the importance of incorporating this source of uncertainty. Projections with temporal variation were similar irrespective of whether data‐derived priors or uniform priors were used. However, the data‐derived priors generated more precise estimates of annual variation that were less sensitive to relaxation of prior constraints. The approach we present can facilitate management decisions at the outset of conservation programmes when risk assessments that account for all relevant uncertainties can be crucial for determining optimal management strategies. [ABSTRACT FROM AUTHOR]

The eradication of invasive predators from islands is a successful technique to safeguard seabird populations, but adequate post‐eradication monitoring of native species is often lacking. The Whenua Hou Diving Petrel (Pelecanoides whenuahouensis; WHDP) is a recently‐described and 'Critically Endangered' seabird, restricted to Codfish Island (Whenua Hou), New Zealand. Invasive predators, considered the major threat to WHDP, were eradicated on Codfish Island in 2000. However, estimates of WHDP population size and trends remain unknown, hindering assessments of the success of the eradications. We collated intermittent burrow counts (n = 20 seasons) conducted between 1978 and 2018. To estimate the population growth rate (λ) before and after predator eradications, we used log‐linear models in a Bayesian hierarchical framework while retrospectively accounting for differences in detection probabilities among burrow counts, due to differences in effort, marking and timing. The number of WHDP burrows was estimated at 40 (36–46) in 1978 and 100 (97–104) in 2018. The pre‐eradication λ was estimated at 1.023 (0.959–1.088), while the post‐eradications λ was estimated at 1.017 (1.006–1.029). The WHDP population appears to be increasing, yet the rate of increase is low compared to other Procellariiformes following predator eradications. The comparatively low post‐eradication λ, combined with an apparent lack of change between pre‐ and post‐eradication λ, indicates that additional threats might be limiting WHDP population growth and that further conservation management is required. The continuation of affordable and simple, albeit imperfect, monitoring methods with retrospective corrections facilitated the assessment of invasive predator eradications outcomes and should guide future management decisions. An abstract in Te Reo Māori (the Māori language) can be found in Appendix S1. [ABSTRACT FROM AUTHOR]

Natal dispersal is a complex behaviour influenced by multiple factors that are often sex-specific and density-dependent. Reintroduced populations are typically low in density in the initial years of establishment; hence, understanding natal dispersal patterns in this context is a critical component of reintroduction biology. Natal dispersal is a key behaviour that influences both the probability of recruitment, and simultaneously dictates the spatial configuration of the reintroduced population as it establishes. Here, we examine natal dispersal in a reintroduced population of an endangered New Zealand forest passerine, the hihi, Notiomystis cincta, in the first 3 years after reintroduction to a large, mature forest reserve. We examined (1) differences between the sexes, and (2) the relationship between temperament and natal dispersal distances (NDD) in locally bred hihi over this time period. We found NDD varied widely in both sexes, with mean NDD significantly higher in males than females. There was a sex-specific effect of temperament, with males that distress-called during handling dispersing further than those that did not. Our results show that while clusters of individuals have established across the reserve due to conspecific attraction, there is movement between these clusters, primarily a consequence of dispersal of males of a distinct temperament. Continuing to monitor natal dispersal patterns as populations establish will provide further insights into the role of dispersal in shaping establishment patterns in reintroduced populations. [ABSTRACT FROM AUTHOR]

Reintroductions of threatened species are increasingly common in conservation. The translocation of a small subset of individuals from a genetically diverse source population could potentially lead to substantial inbreeding depression due to the high genetic load of the parent population. We analysed 12 years of data from the reintroduced population of North Island robins Petroica longipes on Tiritiri Matangi Island, New Zealand, to determine the frequency of inbreeding and magnitude of inbreeding depression. The initial breeding population consisted of 12 females and 21 males, which came from a large mainland population of robins. The frequency of mating between relatives ( f>0; 39%, n=82 pairs) and close relatives ( f=0.25; 6.1%) and the average level of inbreeding ( f=0.027) were within the range reported for other small island populations of birds. The average level of inbreeding fluctuated from year to year depending on the frequency of close inbreeding (e.g. sib–sib pairs). We found evidence for inbreeding depression in juvenile survival, with survival probability estimated to decline from 31% among non-inbred birds ( f=0) to 11% in highly inbred juveniles ( f=0.25). The estimated number of lethal equivalents based on this relationship (4.14) was moderate compared with values reported for other island populations of passerines. Given that significant loss of fitness was only evident in highly inbred individuals, and such individuals were relatively rare once the population expanded above 30 pairs, we conclude that inbreeding depression should have little influence on this robin population. Although the future fitness consequences of any loss of genetic variation due to inbreeding are uncertain, the immediate impact of inbreeding depression is likely to be low in any reintroduced population that expands relatively quickly after establishment. [ABSTRACT FROM AUTHOR]

Carotenoids are essential dietary components utilized not only in pigmentation but also as immuno-stimulants and antioxidants. Reduced availability can have consequences on individual health and survival, thus making carotenoids a good indicator of environmental stress. We compared carotenoid profiles and plumage colour characteristics of an endangered passerine species in New Zealand, between its remnant island source population and two reintroduced island populations. Circulating carotenoids were predominantly lutein (mean of 82.2%) and zeaxanthin (mean of 14.8%), and these were the major carotenoids present as yellow pigments in the males' plumage. There were clear differences in total carotenoid concentrations and plumage colour among the three populations. Circulating carotenoid concentration was significantly higher in one of the reintroduced populations, and the yellow plumage of males was significantly higher in both reintroduced populations in comparison with the remnant population (reflected as a significant increase in hue). Understanding how these differences arise may be of importance to this species given the health benefits carotenoids impart and our ability to select plant species containing these compounds or artificially supplement them. [ABSTRACT FROM AUTHOR]

Targeted threatened species management is a central component of efforts to prevent species extinction. Despite the development of a range of management frameworks to improve conservation outcomes over the past decade, threatened species management is still commonly characterised as ad hoc. Although there are notable successes, many management programs are ineffective, with relatively few species experiencing improvements in their conservation status. We identify underlying factors that commonly lead to ineffective and inefficient management. Drawing attention to some of the key challenges, and suggesting ways forward, may lead to improved management effectiveness and better conservation outcomes. We highlight six key areas where improvements are needed: 1) stakeholder engagement and communication; 2) fostering strong leadership and the development of achievable long-term goals; 3) knowledge of target species' biology and threats, particularly focusing on filling knowledge gaps that impede management, while noting that in many cases there will be a need for conservation management to proceed initially despite knowledge gaps; 4) setting objectives with measurable outcomes; 5) strategic monitoring to evaluate management effectiveness; and 6) greater accountability for species declines and failure to recover species to ensure timely action and guard against complacency. We demonstrate the importance of these six key areas by providing examples of innovative approaches leading to successful species management. We also discuss overarching factors outside the realm of management influence that can help or impede conservation success. Clear recognition of factors that make species' management more straightforward - or more challenging - is important for setting realistic management objectives, outlining strategic action, and prioritising resources. We also highlight the need to more clearly demonstrate the benefit of current investment, and communicate that the risk of under-investment is species extinctions. Together, improvements in conservation practice, along with increased resource allocation and re-evaluation of the prioritisation of competing interests that threaten species, will help enhance conservation outcomes for threatened species., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The effect of tunicamycin (TM) on the metabolism of acetylated low-density lipoprotein (AcLDL) was examined to determine whether N-linked glycosylation is required for the proper function of the AcLDL pathway. Proteolytic degradation of [125I]-AcLDL was increased twofold in the presence of TM. This did not occur via an increase in total lysosomal enzyme activity or extracellular proteolysis; rather, the rate of uptake of [125I]-AcLDL was increased. The enhanced degradation of AcLDL did not lead to a commensurate increase in the rate of synthesis of cholesteryl oleate. Conversely, the rate of cholesterol esterification was reduced in the presence of TM. The uptake of [125I]-AcLDL was more sensitive to inhibition by chloroquine in TM-treated cells. However, the presence of TM did not affect the ability of chloroquine to inhibit constitutive recycling of AcLDL binding sites. These results suggest that N-linked glycosylation may be involved in the regulation of AcLDL metabolism in J774 cells.

Acetyl-LDL (Ac-LDL) bound to transformed mouse macrophage J774 cells in a high affinity, saturable and specific manner. When cells were cultured for 24h in the presence of tunicamycin such that incorporation of N-linked sugars into protein but not protein synthesis itself was inhibited significantly, the binding characteristics of Ac-LDL to the cells were unaltered. In this respect the Ac-LDL receptor of J774 cells is similar to the asialoglycoprotein receptor of HepG2 cells.

The aggressive management of the hanging columella is presented and extends the direct attack on the medial crura to total excision of both medial crura and the overlying vestibular skin. Tip support is maintained.