Background level of risk determines the intensity of predator neophobia in juvenile convict cichlids

Behavioural ecology is rife with examples of prey animals that are able to adjust the intensity of their anti-predator response to match background risk levels. Often, preys need experience with predators before they will invest in costly anti-predator responses. This means that prey animals often fail to respond to predators during their first encounter. Recently, we have shown that prey raised under high-risk conditions may exhibit avoidance of potential predation cues independent of experience (neophobia). Such phenotypically plastic neophobic predator responses may reduce the initial costs of learning ecologically relevant threats while maintaining sufficient behavioural plasticity to respond to variation in local conditions. Here, we test if induced neophobia results in threat-sensitive behavioural trade-offs in response to a novel chemosensory cue. Our first experiment shows that while juvenile convict cichlids (Amatitlania nigrofasciata) pre-exposed to high (but not low) risk conditions exhibited predator avoidance to a novel odour (rainbow trout, Oncorhynchus mykiss), the response intensity was not influenced by the concentration of trout odour detected. Our second experiment demonstrated that the intensity of anti-predator response towards a novel predator cue was dependent upon the level of background risk. Convict cichlids pre-exposed to high-risk conditions showed stronger responses than those pre-exposed to low-risk conditions, while cichlids pre-exposed to intermediate-risk conditions exhibited intermediate response intensities. Together, these data demonstrate that background levels of risk and not the concentration of novel cues detected shape the induced neophobic response pattern of juvenile convict cichlids.     

Use of ecoacoustics to determine biodiversity patterns across ecological gradients

The variety of local animal sounds characterizes a landscape. We used ecoacoustics to noninvasively assess the species richness of various biotopes typical of an ecofriendly forest plantation with diverse ecological gradients and both nonnative and indigenous vegetation. The reference area was an adjacent large World Heritage Site protected area (PA). All sites were in a global biodiversity hotspot. Our results showed how taxa segregated into various biotopes. We identified 65 singing species, including birds, frogs, crickets, and katydids. Large, natural, protected grassland sites in the PA had the highest mean acoustic diversity (14.1 species/site). Areas covered in nonnative timber or grass species were devoid of acoustic species. Sites grazed by native and domestic megaherbivores were fairly rich (5.1) in acoustic species but none were unique to this habitat type, where acoustic diversity was greater than in intensively managed grassland sites (0.04). Natural vegetation patches inside the plantation mosaic supported high mean acoustic diversity (indigenous forests 7.6, grasslands 8.0, wetlands 9.1), which increased as plant heterogeneity and patch size increased. Indigenous forest patches within the plantation mosaic contained a highly characteristic acoustic species assemblage, emphasizing their complementary contribution to local biodiversity. Overall, acoustic signals determined spatial biodiversity patterns and can be a useful tool for guiding conservation.     

An assessment of adherence to basic ecological principles by payments for ecosystem service projects

Programs and projects employing payments for ecosystem service (PES) interventions achieve their objectives by linking buyers and sellers of ecosystem services. Although PES projects are popular conservation and development interventions, little is known about their adherence to basic ecological principles. We conducted a quantitative assessment of the degree to which a global set of PES projects adhered to four ecological principles that are basic scientific considerations for any project focused on ecosystem management: collection of baseline data, identification of threats to an ecosystem service, monitoring, and attention to ecosystem dynamics or the formation of an adaptive management plan. We evaluated 118 PES projects in three markets—biodiversity, carbon, and water—compiled using websites of major conservation organizations; ecology, economic, and climate‐change databases; and three scholarly databases (ISI Web of Knowledge, Web of Science, and Google Scholar). To assess adherence to ecological principles, we constructed two scientific indices (one additive [ASI] and one multiplicative [MSI]) based on our four ecological criteria and analyzed index scores by relevant project characteristics (e.g., sector, buyer, seller). Carbon‐sector projects had higher ASI values (P < 0.05) than water‐sector projects and marginally higher ASI scores (P < 0.1) than biodiversity‐sector projects, demonstrating their greater adherence to ecological principles. Projects financed by public–private partnerships had significantly higher ASI values than projects financed by governments (P < 0.05) and marginally higher ASI values than those funded by private entities (P < 0.1). We did not detect differences in adherence to ecological principles based on the inclusion of cobenefits, the spatial extent of a project, or the size of a project's budget. These findings suggest, at this critical phase in the rapid growth of PES projects, that fundamental ecological principles should be considered more carefully in PES project design and implementation in an effort to ensure PES project viability and sustainability.     

Growth rate and retention of learned predator cues by juvenile rainbow trout: faster-growing fish forget sooner

Under conditions of spatial and/or temporal variability in predation risk, prey organisms often rely on acquired predator recognition to balance the trade-offs between energy intake and risk avoidance. The question of ‘for how long’ should prey retain this learned information is poorly understood. Here, we test the hypothesis that the growth rate experienced by prey should influence the length of the ‘memory window’. In a series of laboratory experiments, we manipulated growth rate of juvenile rainbow trout and conditioned them to recognize a novel predator cue. We subsequently tested for learned recognition either 24 h or 8 days post-conditioning. Our results suggest that trout with high versus low growth rates did not differ in their response to learned predator cues when tested 24 h post-conditioning. However, trout on a high growth rate exhibited no response to the predator cues after 8 days (i.e. did not retain the recognition of the predator odour), whereas trout on a lower growth rate retained a strong recognition of the predator. Trout that differed in their growth rate only after conditioning did not differ in their patterns of retention, demonstrating growth rate after learning does not influence retention. Trout of different initial sizes fed a similar diet (percent body mass per day) showed no difference in retention of the predator cue. Together, these data suggest that growth rate at the time of conditioning determines the ‘memory window’ of trout. The implications for threat-sensitive predator avoidance models are described.     

‘Management Standards’ and work-related stress in Great Britain: Progress on their implementation

The aim of this paper is to identify what constituted barriers to progress in the implementation of the Management Standards for preventing and reducing work-related stress nationally, an approach advocated by the Health and Safety Executive in Great Britain. Data were collected from more than 100 public sector organisations through inspector visits and research interviews. Findings show that under supportive contexts, organisations were able to follow the process of a stepwise method for assessing psychosocial risks and implementing interventions using HSE assessment tools and guidance. Main enabling factors included the active and visible support from senior management, human resource departments, and line managers; regular communications on progress, sufficient organisational capability in terms of resources and expertise; departmental/team level assessment as opposed to an overall corporate wide assessment, and involvement of key stakeholders (e.g. Trade Union, employees). Some of the critical barriers across many public sector organisations included in this study were: major or on-going organisational changes; lack of organisational capability; and the resource intensive aspect of the method requiring focus groups in addition to stress survey data. Implications of the findings for policy development are discussed.     

Determinants of multiple central-place territory use in wild young-of-the-year Atlantic salmon (<Emphasis Type="Italic">Salmo salar</Emphasis>)

Patterns of space use provide key insights into how animals exploit local resources and are linked to both the fitness and distribution of individuals. We studied territory size, mobility, and foraging behavior of young-of-the-year Atlantic salmon Salmo salar in relation to several key environmental factors in Catamaran Brook, New Brunswick, Canada. The 50 study fish were all multiple central-place foragers (i.e., alternated among several sit-and-wait foraging stations) and showed great variability in territory size and the total distance traveled within the territories. Territory size increased with the mean distance traveled between consecutive foraging stations, the number of stations visited, and the mean foraging radius. Fish also varied greatly in how much of the total travel distance was associated with foraging at a station (14.8–91.8%) versus switching among stations (4.6–84.3%). As predicted, fish in slow-flowing waters, where drifting prey were scarce, used larger multiple central-place territories than individuals in faster, more productive waters. Interestingly, however, the most mobile fish did not inhabit slow-running waters as predicted but were found at intermediate (optimal) water current velocities. Hence, our study suggests that among some multiple central-place foragers, increased mobility may not only serve to increase prey encounter rate but may reflect an attempt to patrol territories in favorable habitats. Further studies are needed to determine the generality and the ultimate benefits of multiple central-place space use among stream-dwelling fish and other animals.     

What Use Is Science to Animal Welfare?

   My concern is to question the quality and utility of science in general and ethology in particular as applied to animal welfare. This topic has in the past provoked me to some severe criticism, for example, 'A lot of well-intended welfare research is neither very good science nor very helpful to the animals.... Too much welfare research is (in my opinion) flawed either because it is oversimplistic, or because it is not so much designed to test preconceptions but to reinforce prejudice' (Webster 1994). Dawkins (1997) has recently responded to this challenge, addressing the question 'Why has there not been more progress in welfare research?' Her response is concerned largely with applied ethology. My own criticism was not directed at ethologists in particular. I was more concerned by the misuse of scientific method by those who seek to obtain a so-called 'objective' measurement of something which they preconceive to be a stress (e.g. measurement of plasma concentrations of cortisol or endorphins in animals following transportation). Here the 'objective' measure frequently becomes the test that gives the answer that they want, and if it fails, then they seek other 'objective' markers until they achieve a set of measurements that supports the subjective impression which they had at the outset. My second main concern is that the welfare state of a sentient animal is a very complex affair and cannot be embraced by any single scientific discipline, be it ethology, physiology, molecular or neurobiology. Unfortunately it is also too complex to be embraced by a single-sentence definition. The best I can do is to suggest that it is determined by the capacity of an animal to sustain physical fitness and avoid mental suffering. The assessment of this is necessarily multidisciplinary.     

The Rarest of Darwin's Finches

The Mangrove Finch (Cactospiza heliobates) is unique among Darwin's finches in its specialized habits and naturally fragmented distribution on individual islands. It has been reported to occupy six patches of mangroves separated to varying degrees on two of the Galápagos islands, Isabela and Fernandina. We present the results of a field study in three of the patches. The species appears to have become extinct on Fernandina and to be restricted now to a maximum of four habitat islands on Isabela. In one of them, Playa Tortuga Negra, we estimate the population of breeding adults to be 10–20 pairs. At another, west of Villamil, the population size is probably now small due to the cutting of mangroves. The other two populations, close to each other east of Punta Moreno, probably hold the largest demes. Their status is unknown. We estimate that the genetically effective size of the combined populations is 30–380 individuals. Because the populations are so small and restricted, they are vulnerable to any disturbance of the environment. This has probably been so throughout their history because they inhabit a fragmented habitat in a tectonically active region. New anthropogenic threats this century are an introduced wasp (Polistes versicolor), which may be a predator on a major food item (insect larvae) of the finches, and destruction of the habitat. Protection of the occupied habitat against human exploitation is required for the preservation of the species because no alternative habitat is known.