Catching sharks: recreational saltwater angler behaviours and attitudes regarding shark encounters and conservation

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Correlates of lake use by breeding common scoters in Scotland

1. Many populations of sea‐ducks, which typically winter at sea but breed on fresh water, are declining. Numbers of common scoters Melanitta nigra (L.) breeding in Scotland halved between 1995 and 2007, despite most breeding sites having special conservation status. To identify potential conservation measures, a 3‐year study was conducted, investigating correlates of lake use by scoters. 2. At 26 scoter breeding lakes, food abundance (macroinvertebrates) and foraging habitats (substrates, water depth) were measured, and their associations with scoter lake use explored using multi‐model inference. Correlates of macroinvertebrate abundance (water quality, fish abundance) were also investigated. 3. Averaged over 3 years (2009–2011), these lakes held 26.7 (SE 6.3) females, around half the Scottish breeding population. Scoters occurred more often at lakes having abundant large‐bodied invertebrates and extensive shallow water. Lakes where the average weight of the largest invertebrate in each sample exceeded 4 mg had 9.2 times (females) or 27 times (broods) more scoter records than other lakes. Lakes where water depths (10 m from the shore) averaged less than 1.3 m had 2.5 times (females) or 12 times (broods) more scoter records than other lakes. 4. The abundance of large‐bodied invertebrates was greater where small fish species (mostly three‐spined sticklebacks Gasterosteus aculeatus) were more common and brown trout Salmo trutta were scarcer. 5. Results suggest two approaches to scoter conservation. At lakes used for hydro‐electricity generation, water level regimes that provide extensive shallow water should be tested to see if these benefit scoters. At lakes used for trout fishing, trout reduction by increased angling should be trialled, to see if this increases large‐invertebrate abundance and scoter use. Copyright © 2015 John Wiley & Sons, Ltd.     

Angling for endangered fish: conservation problem or conservation action?

Recreational angling has been implicated in population declines of some marine and freshwater fish, but this activity is rarely considered as a threat or even halted when endangered species are targeted. Indeed, in some cases, anglers are drawn to fish for rare or endangered species. Conservation‐oriented behaviours such as catch‐and‐release are often practiced voluntarily due to the ethics of anglers, yet even in these cases, some fishing mortality occurs. Nonetheless, there are many indirect conservation benefits associated with recreational angling. Here, we present a series of case‐studies and consider whether catch‐and‐release angling for endangered fish is a conservation problem or a conservation action. If recreational angling activities contribute to population‐level consequences that are contrary to recovery strategies, then angling for endangered species would seem to be a poor option. However, as revealed by several case‐studies, there is much evidence that anglers are vocal and effective proponents of fish and habitat conservation, and for endangered species, they are often the only voice when other stakeholders are not engaged. Anglers may contribute directly to conservation actions via user fees (e.g. licences), philanthropic donations or by volunteering in research, education and restoration activities. However, it is important to quantify post‐release mortality as well as understand the full suite of factors influencing a given population or species to know the potential risks. A risk assessment approach outlined in the paper may be used by managers to determine when the benefits of angling for endangered species outweigh the risks.     

Managing outbreaks of invasive species: Eradication versus suppression

Abstract

A framework is developed to evaluate eradication as one of three alternative management responses to an outbreak of an invasive species: eradication, suppression or no action. This framework can be used to establish under what conditions an eradication option could provide an expected net economic benefit, and whether this net benefit exceeds that of the other two options. The eradication option is more likely to be preferred in situations where there is an immediate export benefit that is derived from eradication of the outbreak, and also the uncertainty associated with the likely success of eradication is low.     

Investigation of isomeric transformations of chlorogenic acid in buffers and biological matrixes by ultraperformance liquid chromatography coupled with hybrid quadrupole/ion mobility/orthogonal acceleration time-of-flight mass spectrometry

Ultraperformance liquid chromatography coupled with hybrid quadrupole/ion mobility/orthogonal acceleration time-of-flight (oa-TOF) mass spectrometry (UPLC-IM-MS) was used to study the isomeric transformations of trans-5-caffeoylquinic acid, an extremely active compound present in multiple vegetables, fruits, and beverages. The UPLC/oa-TOF MS results proved that in phosphate buffer (pH 7.4), plasma, or urine sample, trans-5-caffeoylquinic acid first isomerizes to trans-4-caffeoylquinic acid and then to trans-3-caffeoylquinic acid by intramolecular acyl migration. When exposed to UV light, trans-3-, -4-, and -5-caffeoylquinic acids undergo cis/trans isomerization to form cis isomers. The isomerization was solely dependent on the pH of the matrix, as well as the incubation temperature, and was independent of metabolic enzymes. UPLC-IM-MS results revealed that a reversible cis/trans isomerization of caffeoylquinic acids could also be induced by the electric field in an electrospray source. Thus, understanding the possible role of electric field-induced isomerization of caffeoylquinic acids may help lessen the confusion between gas phase phenomena and liquid state chemistry when applying IM-MS analysis. The comprehensive understanding of caffeoylquinic acid isomerization transformations is crucial for the appropriate handling of samples and interpretation of experimental data.     

Measurement of genetic and environmental variation in barley (Hordeum vulgare) grain hardness

In this study, we assessed a broad range of barley breeding lines and commercial varieties by three hardness methods (two particle size methods and one crush resistance method (SKCS—Single-Kernel Characterization System), grown at multiple sites to see if there was variation in barley hardness and if that variation was genetic or environmentally controlled. We also developed near-infrared reflectance (NIR) calibrations for these three hardness methods to ascertain if NIR technology was suitable for rapid screening of breeding lines or specific populations. In addition, we used this data to identify genetic regions that may be associated with hardness. There were significant (p<0.05) genetic effects for the three hardness methods. There were also environmental effects, possibly linked to the effect of protein on hardness, i.e. increasing protein resulted in harder grain. Heritability values were calculated at >85% for all methods. The NIR calibrations, with R² values of >90%, had Standard Error of Prediction values of 0.90, 72 and 4.0, respectively, for the three hardness methods. These equations were used to predict hardness values of a mapping population which resulted in genetic markers being identified on all chromosomes but chromosomes 2H, 3H, 5H, 6H and 7H had markers with significant LOD scores. The two regions on 5H were on the distal end of both the long and short arms. The region that showed significant LOD score was on the long arm. However, the region on the short arm associated with the hardness (hordoindoline) genes did not have significant LOD scores. The results indicate that barley hardness is influenced by both genotype and environment and that the trait is heritable, which would allow breeders to develop very hard or soft varieties if required. In addition, NIR was shown to be a reliable tool for screening for hardness. While the data set used in this study has a relatively low variation in hardness, the tools developed could be applied to breeding populations that have large variation in barley grain hardness.     

Assessing daily egestion rates in earthworms: using fungal spores as a natural soil marker to estimate gut transit time

Earthworms have an important role in ‘bioturbation’—the mixing of soil due to biological processes. Quantification of earthworm bioturbation relies on estimating earthworm egestion rates which in turn depend on two parameters: the gut content of the worms and the gut transit time (GTT). Gut content can be determined relatively easily, but determining GTT is problematic. The present study aimed at estimating daily soil egestion rates of Aporrectodea caliginosa and Lumbricus terrestris, refining the most common approach for estimating GTT by using fungal spores as natural markers in ingested soil. This approach avoids the use of artificial markers that may adversely affect the earthworms. Gut transit time was estimated by tracking the passage of marked soil through the gut by the appearance of the spores in the egested faeces. Gut transit time was estimated to be 9.6?±?0.3 h for A. caliginosa and 11.6?±?0.5 h for L. terrestris. Gut content averaged 465?±?40(± standard error (SE))?mg dw g^?1 dw worm for A. caliginosa and 265?±?80 mg dw g^?1 dw worm for L. terrestris. From these values, daily egestion rates of 1.16 and 0.66 g dw faeces g^?1 dw worm d^?1 were calculated for A. caliginosa and L. terrestris, respectively. Both values compare well to literature values for each species. The presented method for GTT estimation is inexpensive, rapid and easy to evaluate, with spores being a good alternative to existing markers.     

PIT标记技术在幼鲵标记中的应用研究

对347尾预放流幼鲵的尾部皮下层和肌肉层分别进行横向和纵向PIT标记,通过对标记幼鲵6个月的跟踪观察,共收集到脱落芯片94枚,总脱落率高达27.1%,严重影响标记目的。对植入芯片时的记录进行对比分析,得出尾部皮下层纵向植入法对幼鲵肌体伤害最小,脱落率最低,为3.0%,笔者认为该方法是PIT标记幼鲵的最佳方法。     

Complementary use of natural and artificial wetlands by waterbirds wintering in Doñana,south‐west Spain

• 1. The Doñana wetland complex (SW Spain) holds more wintering waterfowl than any other wetland in Europe.
• 2. This study focused on the use made by 12 common waterbirds (eight ducks and four waders) of the natural seasonal marshes in Doñana National Park (DNP) and the adjacent Veta la Palma (VLP) fish ponds created in the early 1990s. Data used were from aerial and terrestrial surveys collected between October and February during six consecutive winters from 1998/99 to 2003/04. Changes in distribution of each bird taxon were related to changes in the extent of flooded marshes within DNP. Up to 295 000 ducks were counted in VLP during dry periods, and up to 770 000 in DNP when it was flooded.
• 3. The timing and extent of flooding in DNP was highly variable, but there was a consistent pattern in which ducks concentrated in VLP during dry months and winters but redistributed to DNP as more of it was flooded. This refuge effect was also strong for black‐tailed godwits Limosa limosa, but much less so for other waders. Waders feed mainly on invertebrates, and invertebrate biomass in VLP was found to be higher than in DNP. Ducks feed mainly on seeds and plant material, which are more abundant in DNP when flooded.
• 4. When water levels in DNP were stable over the course of a winter, or controlled for in multivariate models, the numbers of ducks at VLP declined over time, probably due to reduced availability of plant foods. In contrast, numbers of waders at VLP were more stable, and their invertebrate prey became more abundant over time, at least in the winter 2003/4.
• 5. In this extremely important wetland complex, the value of natural and artificial wetlands for wintering waterbirds are complementary, providing suitable habitat for different species and for different conditions in a highly variable Mediterranean environment.

Copyright © 2009 John Wiley & Sons, Ltd.