A 40-year chronology of the vulnerability of spinetail devil ray (Mobula mobular) to eastern Pacific tuna fisheries and options for future conservation and management

1. Tuna fisheries are among the largest and most valuable fisheries in the world, but most interact with many non-target species, including several of high conservation importance. The spinetail devil ray (Mobula mobular) – listed as ‘Endangered’ on the IUCN Red List of Threatened Species – is a commonly discarded bycatch species, particularly in the eastern Pacific Ocean, yet insufficient data exist to undertake a traditional population assessment.
2. A new ecological risk assessment approach designed for data-limited settings – Ecological Assessment of the Sustainable Impacts of Fisheries (EASI-Fish) – was used to reconstruct the historical vulnerability status of M. mobular and to simulate potential changes in its status under 45 hypothetical conservation and management measures. These involved various temporal closures of the eastern Pacific Ocean tuna fishery, decreasing post-capture mortality by improved handling and release practices, and combinations of the two.
3. The species was classified as ‘Least Vulnerable’ between 1979 and 1993, but became ‘Most Vulnerable’ from 1994, which coincided with a rapid spatial expansion of the industrial purse-seine fishery, and especially from 2011 following the rapid increase in the number of sets made on floating objects. Simulating the conservation and management measures in place in 2018 revealed that 31 of the 45 scenarios resulted in a change in classification of the species to ‘Least Vulnerable’, which primarily involved a reduction of post-capture mortality by as little as 20%.
4. It is fortuitous in that education of fishers to implement appropriate best handling and release practices is simpler, more rapid and more cost-effective than the implementation of fishery closures or gear modifications, which can be expensive and complex to implement and monitor and will probably result in substantial reduction in the catches of target species.

     

Farmers’ Perceptions and Actions to Decrease Crop Raiding by Forest-Dwelling Primates Around a Rwandan Forest Fragment

Human–wildlife conflict (HWC) presents an increasing challenge to conservation, particularly in densely populated parts of low-income countries. This article assessed one form of conflict, crop raiding by forest-dwelling primates, along the boundary of a tropical montane forest fragment (Gishwati Forest) in western Rwanda. Variation in species involved, crops affected, differences in magnitude with season and distance to the forest boundary, and the nature of mitigation efforts were assessed through semi-structured interviews with farmers and field-based observations during June and July 2009. Substantial losses of crops were reported, with replacement costs possibly reaching 10–20% of total household income. Chimpanzees (Pan troglodytes) and Cercopithecus monkeys were the sole reported raiders, mainly affecting maize and legumes. Mitigation was restricted to guarding of crops and modification of farming practices, the latter potentially having significant dietary consequences for subsistence farmers. These findings highlight the potentially high economic costs, and food security effects of HWC.     

A biophysical model to assess the trade‐off between larval recruitment and catch in southern Australia's largest prawn fishery

Data from stock assessment surveys, published research and climate sensors were linked to model the interaction between fishing, physical‐oceanographic processes and spatial patterns of larval settlement for western king prawn [Penaeus (Melicertus) latisulcatus]. This information was used to evaluate the trade‐off between larval recruitment and catch during fishing periods that demand high prices but coincide with spawning. Total rates of larval settlement were maximized when tidal currents and atmospheric physical‐forcing components were coupled with simulations of larval swimming behaviour under average gulf temperatures. Average gulf temperatures sustained longer larval durations and increased larval settlement rates by over 12% compared with warmer gulf conditions simulated under a scenario of global warming. Reproductive data coupled with outputs from the biophysical model identified consistent inter‐annual patterns in the areas contributing to larval settlement success. Areas located in the north‐east, and central‐west of the fishery, consistently contributed to over 40% of all larvae reaching a settlement in each year. Harvest sensitivity analyses indicated that changes in the spatial patterns of pre‐Christmas fishing could lead to improvements in overall rates of the larval settlement while maintaining or improving the levels of catch. Future studies to refine the model inputs relating to physical processes, larval behaviour and mortality rates for P. latisulcatus coupled with surveys of juvenile prawn abundance to ground truth the modelled predictions, would allow stock recruitment relationships to be more closely examined and inform adaptive management of the fishery in the future.     

Preliminary in vivo study on the potential application of a novel method of e-tracking to facilitate traceability in the poultry food chain

The feasibility of using GS1 DataMatrix (GS1 DM) barcodes laser printed onto the beaks of poultry as a possible method of identification and, therefore, traceability of the individual were examined in this study, including a preliminary live trial on layer hens. The optimal laser type and settings for this particular application had been selected during previous in vitro and in vivo trials. GS1 DM barcodes were printed on both sides of the beaks of mature layer hens and read using a high specification camera based 1-Dimensional/2-Dimensional (1-D/2-D) DataMan 7500 barcode reader. The reading procedure was repeated on a number of occasions over a 5 week period to examine the effects of time in a commercial environment on the clarity and readability of the GS1 DM barcode, and the ability of the printed GS1 DM barcodes to resist the physical and chemical challenges of such a setting. The results show a very short timeframe during which all barcodes, both right and left combined, remain readable. Thereafter the readability deteriorates rapidly, due to the growth and healing of the beaks of the layer hens. Results also show that there was no significant difference in the readability between GS1 DM barcodes printed on the right or left side of the beak. The proportion of identification (ι) (i.e. number of layers identifiable by either one or two readable GS1 DM barcodes) was also calculated. All layer hens were fully identifiable for a seven day period by either one or two readable GS1 DM barcodes. Further analysis showed that the proportion of identification (ι) was significantly higher for layer hens when identified with two GS1 DM barcodes as opposed to just one. Secure movement control of live mature poultry at vulnerable points in the food chain, such as transfer of ownership, could well be facilitated by the use of this technology, thereby preventing fraud or substitution at these points.     

Using focus groups to engage veterinary students in course redesign and development

Students' perceptions about the quality of teaching have been shown to influence their approaches to learning and studying. The literature suggests that understanding student perceptions is critical to making informed decisions about curriculum development so that courses meet objectives, enhance engagement, and, ultimately, improve learning. However, the assessment of students' perceptions of their courses and the quality of teaching is frequently limited to an end-of-term course evaluation survey. While these course evaluations may be useful in providing a summative assessment, they do not typically provide insight into the reasons and influences that underlie student ratings. Achieving this type of understanding can be accomplished through qualitative methodology, which is a process of investigation used to reveal the depth, complexity, and nuances of perceptions and experiences. In the current article, we report the use of focus groups as a method of gaining in-depth understanding of student perceptions for course redesign. We present the redesign of the Art of Veterinary Medicine II course, a second-year core offering within the Doctor of Veterinary Medicine curriculum at the Ontario Veterinary College in Guelph, Canada. A series of student focus groups were held to gain greater insight into student perceptions of the course objectives, format, and content. Findings were then considered in the redevelopment of the course to better engage students and their various learning styles. Summative course evaluations as well as informal feedback before and after the focus groups indicate a notable improvement in student experiences and perceptions of the course format and content following the focus-group informed course redesign.     

Fluazifop-p-butyl herbicide: Implications for germination, emergence and growth of Australian plant species

Five experiments were implemented to collect information related to the effects of fluazifop-p-butyl (active chemical in grass selective herbicides, Fusilade^® and Fusilade Forte™) on seed germination, seedling emergence, growth and health of species native to southwest Australia (a grass and non-grasses), together with several co-occurring introduced species (grasses and a non-grass). Experiments investigated effects of herbicide concentrations, seed burial depths, seed-sowing times since herbicide application and application locations (foliage versus soil). Both herbicides, at half to quadruple strength of recommended field application concentrations, adversely affected development of native and introduced species, both grasses and non-grasses. Herbicidal effects were observed during the seed germination phase, and if germination had occurred, during seedling emergence and, finally, during plant establishment. However, effects were more pronounced after seed germination, particularly on development of seedlings and plants, with retardation and/or discoloration of either radicles or shoots. Not unexpectedly, seedlings from seeds buried deeper in the sand medium (20 mm) struggled to emerge. Both herbicides demonstrated residual characteristics by impeding seedling emergence and growth from seeds sown at various dates (up to maximum test duration of 3 weeks) following exposure of the sand medium to the herbicides. Further, herbicide application to sand only, produced effects on 5-6 months old plants that were similar as application to foliage only, demonstrating herbicide uptake from sand. While the findings support independent research, they contradict the purported herbicide characteristics by commercial sources - grass selective, post-emergent, non-residual, rapid breakdown and active through foliar application only. Implications of these herbicides for biodiversity conservation are discussed.     

Student Perceptions of an Online Model for Library Orientation in Agriculture and Related Disciplines

Orienting students to the library, its resources, and its services is a core function of many academic librarians working in public services roles. Librarians often spend considerable time and effort developing face-to-face or online library orientation activities. Many studies have addressed the effectiveness of library orientations on student learning, yet less is known about students' attitudes toward and opinions of these orientations. This study investigated student perceptions and opinions of an online library orientation for agriculture and related disciplines. Our results indicate that students recognize the value of the online library orientation as an important part of their student experience.     

Earthquake‐induced habitat migration in a riparian spawning fish has implications for conservation management

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