Accurate pedigree information is critical to animal breeding systems to ensure the highest rate of genetic gain and management of inbreeding. The abundance of available genomic data, together with development of high throughput genotyping platforms, means that single nucleotide polymorphisms (SNPs) are now the DNA marker of choice for genomic selection studies. Furthermore the superior qualities of SNPs compared to microsatellite markers allows for standardization between laboratories; a property that is crucial for developing an international set of markers for traceability studies. The objective of this study was to develop a high throughput SNP assay for use in the New Zealand sheep industry that gives accurate pedigree assignment and will allow a reduction in breeder input over lambing. This required two phases of development- firstly, a method of extracting quality DNA from ear-punch tissue performed in a high throughput cost efficient manner and secondly a SNP assay that has the ability to assign paternity to progeny resulting from mob mating. A likelihood based approach to infer paternity was used where sires with the highest LOD score (log of the ratio of the likelihood given parentage to likelihood given non-parentage) are assigned. An 84 “parentage SNP panel” was developed that assigned, on average, 99% of progeny to a sire in a problem where there were 3,000 progeny from 120 mob mated sires that included numerous half sib sires. In only 6% of those cases was there another sire with at least a 0.02 probability of paternity. Furthermore dam information (either recorded, or by genotyping possible dams) was absent, highlighting the SNP test’s suitability for paternity testing. Utilization of this parentage SNP assay will allow implementation of progeny testing into large commercial farms where the improved accuracy of sire assignment and genetic evaluations will increase genetic gain in the sheep industry.

Worldwide, studies of interactions between introduced and native bees have produced contradictory evidence regarding the potential for competition. Different resource requirements and the impact of tongue length on resource use are often overlooked aspects of these studies. Here, we examine floral resource use and niche overlap between introduced social bees and native solitary bees over two flowering seasons on The Remarkables mountain range, South Island, New Zealand. The native bee fauna of New Zealand is composed of short‐tongued solitary bees in the families Colletidae and Halictidae. Long‐tongued social bees were introduced 150 years ago, and Apis mellifera and Bombus species are now widespread. We analysed floral resource utilization by introduced bees (mainly Bombus terrestris) and native bees in relation to resource abundance across elevations in montane to alpine grassland communities. We modelled resource utilization and overlap between bee taxa using a novel index of floral resource availability, developed to more accurately describe floral density. Additionally, we sought to quantify the impact of honey bees by introducing hives, however, low densities in study plots prevented direct conclusions from being drawn. Native and introduced bees did, however, have distinctly different floral preferences over the flowering season with more niche overlap within, rather than between, native and introduced groups. Introduced bees showed a preference for introduced species in the family Fabaceae which native bees could not access. Native bees heavily utilized introduced Asteraceae as well as native floral resources that introduced bees did not prefer. The limited resource overlap between bee taxa indicated that bee communities in New Zealand may have reduced potential for competition, owing to the different resource requirements of solitary versus social bees and their differing abilities to access floral resources. These findings provide some potential explanations for contradictory evidence worldwide regarding the perceived detrimental impacts of introduced social bees.

No abstract

On temperate rocky reefs, overexploitation of high‐trophic‐level omnivores can result in the decimation of kelp forest habitats by releasing sea urchin population networks from top‐down control. However, the local dynamics of the resulting trophic cascades are context‐dependent. Here, we investigate the community‐wide patterns associated with both diffuse stressors and localized protection of high‐trophic‐level omnivores in kelp forest ecosystems by comparing communities among marine reserves and fished areas in two contrasting regions in terms of fishing intensity and land‐based stressors, Fiordland and the Marlborough Sounds, New Zealand. We find higher densities of the potential sea urchin predators, red rock lobsters (Jasus edwardsii) and banded wrasse (Notolabrus fucicola), in the Fiordland region, and larger effect sizes of fishing on the exploited fish communities in the Marlborough Sounds. Patterns in sea urchin density were consistent with the idea that high‐trophic‐level species, such as large fish and rock lobsters, regulate sea urchin population density, with lower densities of Evechinus chloroticus observed inside marine reserves, in both regions. Nevertheless, densities of E. chloroticus were generally high (>3 m2) in the Marlborough Sounds, likely above a grazing threshold in both fished and reserve sites. The proportion of habitat where sea urchins were absent was 29% in Marlborough Sounds and 90% in Fiordland. Consequently, we observe 49% barren habitat in Fiordland vs. 70%, and a larger effect of fishing on kelp community structure, in the Marlborough Sounds, where fishing effect sizes and land‐based stressors were more severe. We propose that a combination of diffuse stressors including regional overexploitation of important sea urchin predators, sedimentation, and warming of coastal waters likely contributed to regional differences in the responses of trophic interaction chains to localized reductions in fishing within marine reserves. The present study highlights how physiologically stressed and modified kelp forest ecosystems are more susceptible to detrimental phase shifts at a regional spatial scale.

With the increasingly imperilled status of shark populations, there is a pressing need to evaluate management solutions. Given the threats posed by fishing, marine reserves (MRs) present a promising option. Ata Whenua (Fiordland) in the South Island of Aotearoa/New Zealand is an ideal location to investigate this phenomenon owing to the presence of several shark species in coastal MRs. One‐hundred and sixty‐seven baited remote underwater video deployments were made in five MRs. A multi‐model inference approach using generalized linear modelling was used to assess the combined effect of the MRs on two trophic groups of coastal sharks. Generalized linear modelling was used to assess the effect of protection on, firstly, the presence of broadnose sevengill sharks (Notorynchus cepedianus), while accounting for variations in environmental variables, and secondly, the combined relative abundance of mesopredatory sharks detected (spiny dogfish, Squalus acanthias; school shark, Galeorhinus galeus; and carpet shark, Cephaloscyllium isabellum). Mesopredators had a higher relative abundance in MRs by a factor of 2.5 and there was a strong significant effect of protection, suggesting that MRs have led to an increase in their abundance or a change in distribution. In contrast, there was no effect of protection detected for sevengill sharks. It is concluded that the relatively small (<40 km2) MRs sampled do not provide conservation benefits for a large, mobile shark, but that they are potentially large enough to offer protection for mesopredatory sharks with smaller home ranges. To be effective for shark conservation, we therefore recommend that MRs need to be appropriately sized for the ranging behaviour of the target species for protection.

No abstract

In an enclosed glasshouse with sucrose provisioned artificial flowers, we observed nectar-foraging bumble bees and honey bees under several resource conditions to determine potential for displacement. Different responses were displayed for varying resource treatments. Overall, bumble bees did not show reduced foraging in the presence of honey bees. When resources were reduced, bumble bees did not change their foraging behavior, whereas honey bees responded by decreasing their visitation rate. When a food resource of higher quality was introduced, bumble bee foragers shifted their foraging effort to the high-quality resources, whereas honey bees continued to forage on the lower quality resources they had been foraging on. We discuss these results by considering how the individual strategy of bumble bees compared with the colony-based strategy of honey bees may explain observed differences and highlight the potential advantages of each strategy in the natural environment. honey bees / bumble bees / artificial flowers / foraging / competition