Securing the Demographic and Genetic Future of Tuatara through Assisted Colonization

Abstract: Climate change poses a particular threat to species with fragmented distributions and little or no capacity to migrate. Assisted colonization, moving species into regions where they have not previously occurred, aims to establish populations where they are expected to survive as climatic envelopes shift. However, adaptation to the source environment may affect whether species successfully establish in new regions. Assisted colonization has spurred debate among conservation biologists and ecologists over whether the potential benefits to the threatened species outweigh the potential disruption to recipient communities. In our opinion, the debate has been distracted by controversial examples, rather than cases where assisted colonization may be a viable strategy. We present a strategic plan for the assisted migration of tuatara (Sphenodon punctatus), an endemic New Zealand reptile. The plan includes use of extant populations as reference points for comparisons with assisted‐colonization populations with respect to demography, phenotypic plasticity, and phenology; optimization of genetic variation; research to fill knowledge gaps; consideration of host and recipient communities; and inclusion of stakeholders in the planning stage. When strategically planned and monitored, assisted colonization could meet conservation and research goals and ultimately result in the establishment of long‐term sustainable populations capable of persisting during rapid changes in climate.     

Incorporating Climate and Ocean Change into Extinction Risk Assessments for 82 Coral Species

Many marine invertebrate species facing potential extinction have uncertain taxonomies and poorly known demographic and ecological traits. Uncertainties are compounded when potential extinction drivers are climate and ocean changes whose effects on even widespread and abundant species are only partially understood. The U.S. Endangered Species Act mandates conservation management decisions founded on the extinction risk to species based on the best available science at the time of consideration—requiring prompt action rather than awaiting better information. We developed an expert‐opinion threat‐based approach that entails a structured voting system to assess extinction risk from climate and ocean changes and other threats to 82 coral species for which population status and threat response information was limited. Such methods are urgently needed because constrained budgets and manpower will continue to hinder the availability of desired data for many potentially vulnerable marine species. Significant species‐specific information gaps and uncertainties precluded quantitative assessments of habitat loss or population declines and necessitated increased reliance on demographic characteristics and threat vulnerabilities at genus or family levels. Adapting some methods (e.g., a structured voting system) used during other assessments and developing some new approaches (e.g., integrated assessment of threats and demographic characteristics), we rated the importance of threats contributing to coral extinction risk and assessed those threats against population status and trend information to evaluate each species’ extinction risk over the 21st century. This qualitative assessment resulted in a ranking with an uncertainty range for each species according to their estimated likelihood of extinction. We offer guidance on approaches for future biological extinction risk assessments, especially in cases of data‐limited species likely to be affected by global‐scale threats. Incorporación del Cambio Climático y Oceánico en Estudios de Riesgo de Extinción para 82 Especies de Coral     

Selective Breeding Programs for Rare Alleles: Examples from the Przewalski''s Horse and California Condor Pedigrees

As extinction due to loss of habitat grows more imminent for a wide variety of species, population management has been recognized as an important means toward species survival and recovery in the wild. Genetic management practices generally seek to preserve population variation at the level of the genome. It has been proposed, however, that such efforts should instead be directed to specific loci harboring alleles with particular selective benefits. This strategy may in fact result in greater loss of variation in the rest of the genome, potentially threatening population viability. Pedigrees of Przewalski's horse ( Equus prezewalskii ) and the California Condor ( Gymnogyps californianus ) were used to evaluate a "rare kinship" management strategy in which a single individual known to carry a unique allele is repeatedly bred to mates chosen by mean kinship in order to increase the frequency of the rare allele. This strategy led to increased population mean kinship and reduced gene diversity and founder genome equivalents relative to a no-management control pedigree and performed considerably worse than a pedigree managed for mean kinship. Reduced success in the breeding program can be directly attributed to significant deviations of founders' representations from their respective target values. As a result, a strategy for increasing the frequency of rare alleles cannot be generally recommended for management of captive populations. Under strict conditions, however, limited use of this strategy may be applicable only if used for a short time under careful monitoring by pedigree analysis. Even if these conditions are met, managing by a more conventional method such as mean kinship is preferable. These results illustrate the utility of thoughtful analysis of pedigree information to successful population management.     

Variation in nesting patterns affecting nest temperatures in two populations of painted turtles (<Emphasis Type="Italic">Chrysemys picta</Emphasis>) with temperature-dependent sex determination

Mechanisms maintaining sex ratios in populations with temperature-dependent sex determination (TSD) remain elusive. Although geographic variation in embryonic sex determination (i.e., pivotal temperature) has been widely investigated in reptiles exhibiting TSD, no previous studies have directly addressed geographic variation in maternal behavior affecting nest thermal conditions. I evaluated patterns of nest-site selection and its effects on thermal and hydric nest conditions for a population of painted turtles ( Chrysemys picta bellii) exhibiting TSD in New Mexico. These results are compared to data collected from a well-studied, conspecific population experiencing relatively cooler climatic conditions in Illinois. Since canopy vegetation cover reduces nest temperatures in Illinois, I expected females in New Mexico to nest under high amounts of canopy vegetation cover. However, females from New Mexico placed nests under significantly less canopy vegetation cover, but closer to standing water, than did females from Illinois. Experimental nests in New Mexico demonstrated that increased canopy vegetation cover and soil moisture reduced nest temperatures. By nesting close to standing water rather than under canopy vegetation cover, females in New Mexico nested in habitats more closely associated with maximizing moisture around nests rather than reducing nest temperatures through shading. Mean July nest temperatures were similar for both populations. Since nest hydric conditions affect hatching success and hatchling size in C. picta, nesting patterns in New Mexico may primarily reflect selection for microhabitats affecting offspring survivorship or size.     

A laboratory investigation of the effectiveness of various skin and surface decontaminants for aliphatic polyisocyanates

Isocyanates may cause contact dermatitis and respiratory sensitization leading to asthma. Dermal exposure to aliphatic isocyanates in auto body shops is very common. However, little is known about the effectiveness of available commercial products used for decontaminating aliphatic polyisocyanates. This experimental study evaluated the decontamination effectiveness of aliphatic polyisocyanates for several skin and surface decontaminants available for use in the auto body industry. The efficiency of two major decontamination mechanisms, namely (i) consumption of free isocyanate groups via chemical reactions with active hydrogen components of the decontaminant and (ii) physical removal processes such as dissolution were studied separately for each decontaminant. Considerable differences were observed among surface decontaminants in their rate of isocyanate consumption, of which those containing free amine groups performed the best. Overall, Pine-Sol(R) MEA containing monoethanolamine was the most efficient surface decontaminant, operating primarily via chemical reaction with the isocyanate group. Polypropylene glycol (PPG) had the highest physical removal efficiency and the lowest reaction rate with isocyanates. All tested skin decontaminants performed similarly, accomplishing decontamination primarily via physical processes and removing 70-80% of isocyanates in one wiping. Limitations of these skin decontaminants are discussed and alternatives presented. In vitro testing using animal skins and in vivo testing with field workers are being conducted to further assess the efficiency and identify related determinants.     

Case study: Building an ISO 14001-compatible EMS at Mead Coated Board,Mahrt Mill

Many companies are using ISO 14001 as a guide in formalizing their environmental management system (EMS). This article presents Mead Coated Board, Mahrt Mill's experiences in this process, which involved undertaking a gap analysis and developing the key elements and specific procedures that comprise the EMS. Specific issues addressed include the various techniques and approaches used for developing procedures based on the type and level of procedure required; the interaction between the consultants and the mill personnel; the methods for capitalizing on the experience and expertise of the consultant and the internal personnel to achieve the desired results and lessons learned in the process.     

Predator stimuli and calling behavior of Carolina chickadees (Poecile carolinensis), tufted titmice (Baeolophus bicolor), and white-breasted nuthatches (Sitta carolinensis)

Evidence from different chickadee species (Poecile genus) indicates that birds can modify the note composition of their “chick-a-dee” calls in the presence of predator stimuli. Here, we tested the effects of predator models and the distance of those models on calls of three species foraging together at feeding stations: Carolina chickadees (Poecile carolinensis) and tufted titmice (Baeolophus bicolor), both members of the Paridae family, and white-breasted nuthatches (Sitta carolinensis), a member of the Sittidae family. Model and distance affected seed-taking rates in all three species. “Chick-a-dee” calling rates were higher in the predator context for both chickadees and titmice, but we detected no predator context effects on “quank” call rates for nuthatches. Predator and distance contexts affected acoustic parameters of notes of the “chick-a-dee” calls of chickadees and titmice; no such effects were detected for nuthatch “quank” calls. These results suggest species differences in encoding of information in the primary social calls of these three species that commonly occur in multi-species flocks. Chickadees and titmice are “nuclear” species and nuthatches are “satellite” species, and these different roles might be related to the differences in vocal signaling that we detected.     

Mercury source zone identification using soil vapor sampling and analysis

Development and demonstration of reliable measurement techniques that can detect and help quantify the nature and extent of elemental mercury (Hg(0)) in the subsurface are needed to reduce uncertainties in the decision-making process and increase the effectiveness of remedial actions. We conducted field tests at the Y-12 National Security Complex in Oak Ridge, Tennessee, USA, to determine if sampling and analysis of Hg(0) vapors in the shallow subsurface (<0.3 m depth) can be used to as an indicator of the location and extent of Hg(0) releases in the subsurface. We constructed a rigid polyvinyl chloride push probe assembly, which was driven into the ground. Soil gas samples were collected through a sealed inner tube of the assembly and were analyzed immediately in the field with a Lumex and/or Jerome Hg(0) analyzer. Time-series sampling showed that Hg vapor concentrations were fairly stable over time, suggesting that the vapor phase Hg(0) was not being depleted and that sampling results were not sensitive to the soil gas purge volume. Hg(0) vapor data collected at over 200 push probe locations at 3 different release sites correlated very well to areas of known Hg(0) contamination. Vertical profiling of Hg(0) vapor concentrations conducted at two locations provided information on the vertical distribution of Hg(0) contamination in the subsurface. We conclude from our studies that soil gas sampling and analysis can be conducted rapidly and inexpensively at large scales to help identify areas contaminated with Hg(0).