Identification of weta foraging on brodifacoum bait and the risk of secondary poisoning for birds on Quail Island, Canterbury, New Zealand

Brodifacoum is a second-generation anticoagulant used for rodent control in New Zealand. Concerns about the poisoning of non-target species have resulted in restrictions being imposed on the mainland. It is, however, still commonly employed on offshore islands. Previous research investigating the poisoning risks of brodifacoum has generally focused on birds eating brodifacoum bait (primary poisoning) or through depredation of live rodents or carrion containing brodifacoum residues (secondary poisoning). Other research has highlighted the potential for secondary poisoning of birds via the consumption of contaminated invertebrates. An inspection of rodent bait stations undertaken on Quail Island revealed that both cave and ground weta were feeding on brodifacoum bait. A sample of ground weta (Hemiandrus n. sp.) and cave weta (Pleioplectron simplex) was removed from Quail Island and exposed to toxic bait for 60 days. These weta were then assayed for brodifacoum residues and the values used to quantify the secondary poisoning risk for bird species found around Quail Island. We also calculated the risk to birds of secondary poisoning from the tree weta (Hemideina ricta) and the risk of primary poisoning via direct consumption of brodifacoum bait. The LD50 estimates indicated a low risk of secondary poisoning from contaminated ground weta and cave weta. By contrast, the estimates indicated a higher risk from larger-bodied tree weta; however, our calculations were based on a single residue concentration value and should be treated with caution. Of most concern was the primary poisoning risk from the brodifacoum bait. The results indicated that all the 17 bird species assessed are more susceptible to primary poisoning than secondary poisoning and access to brodifacoum bait by non-target bird species needs to be minimised

An improved 1080 paste for control of possums (Trichosurus vulpecula)

A new 1080 paste (PTP) was developed by Pest-Tech Ltd. and then evaluated in a series of comparative trials with Pestoff possum paste (POP). The research indicated that PTP was significantly more palatable to captive possums than POP following 57 h of exposure to ‘hot’ conditions (hot conditions were 30°C for 6 h followed by 18 h at 13°C on a 24 h cycle). Acceptance by bees was low with significantly less PTP than POP removed by forager bees over a 30 h period. In the field, the control efficacy of both pastes was high (89%-94% kill), with no significant differences between treatments. Based on these results, it is recommend that PTP is registered for possum control in New Zealand

Compensation: The American Way

This paper depicts a picture of American compensation systems and practices in light of concerns for equitable treatment of workers. It raises questions about these practices in reference to racial, gender, and executive pay levels in the U.S., and points out that the principle of equity applied regularly has fallen short when interests and needs of particular groups have been examined. Addressing this shortfall in relation to equity concerns is the key policy challenge facing the American compensation manager

Rodent control and island conservation

Most rodent species are highly adapted, selected, boom-or-bust strategists. Such pre-adaptation to invasiveness allows them quickly to take advantage of abundant new resources and is why rodents are among the most successful mammalian colonizers of islands. This chapter discusses the impacts of alien invasive rodents on natural ecosystems, with emphasis on oceanic islands, and review management techniques to mitigate their effects

Lateral cephalometric analysis of asymptomatic volunteers and symptomatic patients with and without bilateral temporomandibular joint disk displacement

Few studies of dentofacial and orthodontic structural relationships relative to temporomandibular joint (TMJ) dysfunction have been reported. We undertook this investigation to determine any correlation of orthodontic and dentofacial characteristics with TMJ bilateral disc displacement. The population of patients was selected from a TMJ clinic where a control group of asymptomatic volunteers had been previously established and standardized. Differences in skeletal structural features were determined among three study groups: (1) asymptomatic volunteers with no TMJ disk displacement, (2) symptomatic patients with no TMJ disc displacement, and (3) symptomatic patients with bilateral TMJ disk displacement. Thirty-two asymptomatic volunteers without disk displacement (25 female, 7 male) were compared with the same number each of symptomatic patients without TMJ disk displacement and symptomatic patients with bilateral TMJ disk displacement. All subjects had undergone a standardized clinical examination, bilateral TMJ magnetic resonance imaging, and lateral cephalometric radiographic analysis. The groups were matched according to sex, TMJ status, age, and Angle classification of malocclusion. Seventeen lateral cephalometric radiographic cranial base, maxillomandibular, and vertical dimension variables were evaluated and compared among the study groups. The mean angle of SNB, or the intersection of the sella-nasion plane and the nasion–point B line (indicating mandibular retrognathism relative to cranial base), of the symptomatic patients-with-displacement group was significantly smaller than that in the asymptomatic volunteers and symptomatic patients without bilateral disk displacement (p \u3c 0.05). Female subjects showed smaller linear measurements of mandibular length, lower facial height, and total anterior facial height than male subjects in all three groups (p \u3c 0.05). The mean angle of ANB, or the intersection of the nasion–point A and nasion–point B planes (indicating retrognathism of mandible relative to maxilla), was significantly greater in female than in male subjects, in all groups (p \u3c 0.05). Symptomatic patients with bilateral disk displacement had a retropositioned mandible, indicated by a smaller mean SNB angle compared with that in asymptomatic volunteers and symptomatic patients with no disk displacement on either side. Lateral cephalometric radiographic assessment may improve predictability of TMJ disk displacement in orthodontic patients but is not diagnostic; nor does the assessment explain any cause-and-effect relationship. (Am J Orthod Dentofacial Orthop 1998;114:248-55.

Summer home range size and population density of great spotted kiwi (Apteryx Haastii) in the North Branch of the Hurunui River, New Zealand

Home range size, travel distances, and population density of the great spotted kiwi (Apteryx haastii) were investigated in the North Branch of the Hurunui River. Radio tracking was conducted on 10 great spotted kiwi between Dec 2007 and Apr 2008. The estimated minimum home-range sizes were determined using the concave polygon method and ranged between 19.6 ha and 35.4 ha, with a mean of 29.3 ha (± 1.6 SEM). The observed nightly distances travelled per hour varied from 7 to 433 m (n = 569). Most estimates of travel distances (73%) were clustered in the classes from 0 - 150 m/hour, and distances over 200 m/hour were seldom achieved (only c. 7% of distances). The kiwi population in the Mainland Island site on the western North Branch of the Hurunui River was estimated to hold around 290 birds in total. Population density for the entire North Branch area was estimated to be 2 pairs/km² and when including subadults, 5 birds/km². Our estimate of home range size is larger but with more variation than found in other studies. Differences in population density estimates between our study and those in the Hurunui and Arthurs Pass district may be due to different objectives and method

The nuclear pore complex has entered the atomic age

Nuclear pore complexes (NPCs) perforate the nuclear envelope and represent the exclusive passageway into and out of the nucleus of the eukaryotic cell. Apart from their essential transport function, components of the NPC have important, direct roles in nuclear organization and in gene regulation. Because of its central role in cell biology, it is of considerable interest to determine the NPC structure at atomic resolution. The complexity of these large, 40–60 MDa protein assemblies has for decades limited such structural studies. More recently, exploiting the intrinsic modularity of the NPC, structural biologists are making progress toward understanding this nanomachine in molecular detail. Structures of building blocks of the stable, architectural scaffold of the NPC have been solved, and distinct models for their assembly proposed. Here we review the status of the field and lay out the challenges and the next steps toward a full understanding of the NPC at atomic resolution.Pew Charitable Trusts (Scholars Program)National Institutes of Health (U.S.) (Grant GM077537

Bulk Fermi surface coexistence with Dirac surface state in Bi2_2Se3_3: a comparison of photoemission and Shubnikov-de Haas measurements

Shubnikov de Haas (SdH) oscillations and Angle Resolved PhotoEmission Spectroscopy (ARPES) are used to probe the Fermi surface of single crystals of Bi2Se3. We find that SdH and ARPES probes quantitatively agree on measurements of the effective mass and bulk band dispersion. In high carrier density samples, the two probes also agree in the exact position of the Fermi level EF, but for lower carrier density samples discrepancies emerge in the position of EF. In particular, SdH reveals a bulk three-dimensional Fermi surface for samples with carrier densities as low as 10^17cm-3. We suggest a simple mechanism to explain these differences and discuss consequences for existing and future transport studies of topological insulators.Comment: 5 mages, 5 figure

The surface-state of the topological insulator Bi2_2Se3_3 revealed by cyclotron resonance

To date transport measurements of topological insulators have been dominated by the conductivity of the bulk, leading to substantial difficulties in resolving the properties of the surface. To this end, we use high magnetic field, rf- and microwave-spectroscopy to selectively couple to the surface conductivity of Bi$_2$Se$_3$ at high frequency. In the frequency range of a few GHz we observe a crossover from quantum oscillations indicative of a small 3D Fermi surface, to cyclotron resonance indicative of a 2D surface state

Predator-Free New Zealand 2050: Techniques for Improving Ground-based Control and Monitoring of the Brushtail Possum

The brushtail possum, a marsupial native to Australia, was widely introduced in New Zealand (NZ) to develop a fur industry. Before the settlement of humans in NZ, there were no terrestrial mammals; therefore, the local species evolved without mammalian predators. This resulted in native species populations declining at alarming rates and many possibly facing extinction on the NZ mainland, especially large-bodied endemic birds. In response to this problem, private investors (supported by the NZ government) developed an initiative to eradicate key mammal predators (possums, rats, and stoats) on the NZ mainland by 2050 (PFNZ2050). As a result, control efforts have significantly expanded over the past decade, and there are now 17 PFNZ2050 landscape projects covering 757,000 ha. Research has looked at combining audio, visual and social lures to improve control efforts for possums. Early results indicate that a combination of lures increases both encounter and interaction rates around control devices. In particular, the combination of audio and visual lures was consistently the top performer in both captive and small-scale field trials. Large-scale field trials are currently underway to confirm these initial results, investigating the effectiveness of combination lures paired with multi-kill AT220 possum traps. Additionally, the lures are being assessed at different times of the year and with varying possum densities. With the drive to PFNZ2050, pest mammal monitoring has markedly increased as researchers attempt to evaluate competing management control strategies. Traditionally, this has relied on single-use plastic monitoring devices such as chewcards and tracking tunnels. An investigation of pest-animal interaction with chewcards indicates that approximately 12% of plastic deployed ends up as microplastic pollution. Another NZ government initiative seeks to ban all single-use plastics, and research is currently investigating the efficacy of non-plastic (biodegradable) alternatives. This research also includes a cost-effectiveness analysis and the reliability of identifying animal bite marks on both plastic and non-plastic chewcards