Isolation and characterization of microsatellite loci in wild and domestic turkeys (Meleagris gallopavo)

We describe the isolation, development and application of seven microsatellite loci in the eastern wild turkey, Meleagris gallopavo silvestris, as well as their amplification and levels of polymorphism in the domestic turkey. The number of alleles per locus ranged from 5 to 15 and average heterozygosity was high for almost all loci. Domestic turkeys showed significantly reduced numbers of alleles per locus and overall heterozygosities when compared to eastern wild turkeys. The high variability in these markers should provide the level of resolution required to continue studies of wild turkey population genetics.     

The twin-arginine translocation system and its capability for protein secretion in biotechnological protein production

The biotechnological production of recombinant proteins is challenged by processes that decrease the yield, such as protease action, aggregation, or misfolding. Today, the variation of strains and vector systems or the modulation of inducible promoter activities is commonly used to optimize expression systems. Alternatively, aggregation to inclusion bodies may be a desired starting point for protein isolation and refolding. The discovery of the twin-arginine translocation (Tat) system for folded proteins now opens new perspectives because in most cases, the Tat machinery does not allow the passage of unfolded proteins. This feature of the Tat system can be exploited for biotechnological purposes, as expression systems may be developed that ensure a virtually complete folding of a recombinant protein before purification. This review focuses on the characteristics that make recombinant Tat systems attractive for biotechnology and discusses problems and possible solutions for an efficient translocation of folded proteins.     

Assisted colonization as a climate change adaptation tool

Assisted colonization is a form of conservation translocation which introduces species at risk from extinction to new habitats, beyond their current range, in anticipation of more suitable conditions. Identifying which species, communities and ecosystems may benefit most from assisted colonization in coming decades is a key goal for conservation. Climate change is expected to lead to the loss or movement of suitable habitat for a range of species and anticipating which can be effectively conserved through assisted colonization is critical. Here, we identify a series of scenarios that may predispose terrestrial species to the need for assisted colonization in order to reduce extinction risk resulting from anthropogenic climate change and assemble a list of traits commonly associated with at‐risk species. These traits may help to provide broad‐scale guidance on how to select species to target for assisted colonization as a conservation management response to climate change. We also identify six key themes associated with successful conservation translocations including recipient site selection and preparation, a clear understanding of species biology and ecology, and taking lessons from invasive species research.     

TRANSLOCATION OF 14C IN MACROCYSTIS INTEGRIFOLIA (PHAEOPHYCEAE)1,2

Translocation patterns in the giant kelp, Macrocystis integrifolia Bory, were investigated in situ using ¹⁴C tracer; sources and sinks were identified. Export was first detected after 4 h of labeling; experiments were routinely 24 h continuous ¹⁴C application. Mature blades exported ¹⁴C to young blades on the same frond and on younger fronds, as well as to sporophylls and frond initials at the bases of the fronds. Blades <0.3 m from the apex imported and did not export; this distance did not change seasonally. In spring export from blades 0.3–1.25 m from the apex was exclusively upwards; older blades also exported downwards. In fall downward export began 0.5 m from the apex, and blades >2 m from the apex exported exclusively downwards. Carbon imported by frond initials, young fronds, and sporophylls in fall may partly be stored for growth in early spring. No translocation was seen in very young plants until one blade (secondary frond initial) bad been freed from the apical blade; this blade exported to the apical blade for a time, but imported when it began to develop into a frond. The second and third formed blades on the primary fronds (sporophylls also exported when <0.3 m from the apex, and later stopped. Frond initials and sporophylls on later-formed fronds did not export at all. The translocation pattern in M. integrifolia differs from that previously reported in M. pyrifera in seasonal change and in distances from the apex at which the changes take place.     

Can reintroductions to degraded habitat succeed? A test using the common brushtail possum

Habitat degradation contributes to species decline, and habitat quality is an important factor influencing reintroduction success globally. Habitat quality can include a range of physical resources such as nest sites and food resources but also anything that can restrict the use of these resources such as predation risk or competition. In arid Australia, introduced predators are thought to be the primary cause of mammal extinction and reintroduction failure although habitat clearance and alteration are also major causes of population decline. Common brushtail possums are one arid Australian marsupial close to regional extinction. To understand whether habitat quality was limiting their recovery, we reintroduced 148 possums into an area where introduced red foxes were controlled but historic overgrazing had degraded the habitat. We measured both direct (hollow availability, midstorey cover and high‐quality plant foods) and indirect (survival, condition, reproduction, movement) measures of habitat quality. Sixty‐seven released possums and 26 post‐release recruits were radiocollared for up to 2 years after release. Post‐release survival of radiocollared possums was high after 12 months (0.70), and there were no deaths from starvation. Predation by feral cats was the most common cause of mortality, and the open, degraded habitat may have exacerbated predation risk. Continuous breeding, good body condition and comparative home ranges with other sites suggested that food resources were not limiting. Possums used natural tree hollows in Eucalyptus spp. with no use of artificial nest boxes. Results suggest that historically degraded habitat was not a barrier to short‐term reintroduction success when foxes were controlled and natural tree hollows were plentiful. However, demographic data on hollow‐bearing tree species suggest a possible future decline in availability of hollows. These factors, combined with the unknown effects of drought, and synergistic effects of predation and poor quality habitat, suggest long‐term reintroduction success may require improved habitat and cat control.