A framework for engaging stakeholders on the management of alien species

Alien species can have major ecological and socioeconomic impacts in their novel ranges and so effective management actions are needed. However, management can be contentious and create conflicts, especially when stakeholders who benefit from alien species are different from those who incur costs. Such conflicts of interests mean that management strategies can often not be implemented. There is, therefore, increasing interest in engaging stakeholders affected by alien species or by their management. Through a facilitated workshop and consultation process including academics and managers working on a variety of organisms and in different areas (urban and rural) and ecosystems (terrestrial and aquatic), we developed a framework for engaging stakeholders in the management of alien species. The proposed framework for stakeholder engagement consists of 12 steps: (1) identify stakeholders; (2) select key stakeholders for engagement; (3) explore key stakeholders' perceptions and develop initial aims for management; (4) engage key stakeholders in the development of a draft management strategy; (5) re-explore key stakeholders' perceptions and revise the aims of the strategy; (6) co-design general aims, management objectives and time frames with key stakeholders; (7) co-design a management strategy; (8) facilitate stakeholders' ownership of the strategy and adapt as required; and (9) implement the strategy and monitor management actions to evaluate the need for additional or future actions. In case additional management is needed after these actions take place, some extra steps should be taken: (10) identify any new stakeholders, benefits, and costs; (11) monitor engagement; and (12) revise management strategy. Overall, we believe that our framework provides an effective approach to minimize the impact of conflicts created by alien species management

A new species of Zygaspis (Reptilia: Squamata: Amphisbaenidae) from north-eastern Mozambique

We describe a new species of Zygaspis based on a single specimen collected in north-eastern Mozambique and deposited in the Natural History Museum of Zimbabwe, Bulawayo. The new species is characterised by its extensively black pigmentation, 191 body annuli, discrete preoculars, four parietals, two postoculars, three supralabials, and two post-supralabials. Phylogenetic analysis of mtDNA suggests that it is a sister taxon to the widespread Zygaspis quadrifrons

Historical perspectives on global exports and research of African clawed frogs (Xenopus laevis)

Trade in live animals has been associated with populations of invasive species as well as the spread of disease. The African clawed frog, Xenopus laevis, was exported from its native region of southern Africa for use in pregnancy testing, and later for laboratory use as the model amphibian. We use historical export figures and publication records to detail the size and extent of the global trade. In addition, we explore the link between exports, scientific use, and invasive populations and chytrid outbreaks. Exports reached 400 000 animals in the first 30 years from 1940, but only 86 000 were sent outside Africa. Exports out of Africa peaked in the 1950s, while scientific publications using Xenopus laevis grew in the 1970s, coinciding with a rise in invasive populations and chytrid outbreaks. We show a lag between exports of Xenopus laevis and a rise in invasive populations of around 15 years. Our data demonstrate the global reach of the exports of Xenopus laevis from South Africa, and a later, much wider distribution via the scientific network which was supplied by secondary means outside of South Africa. We contend that our data demonstrate that by 1970, Xenopus laevis was the world’s most widely distributed amphibian: institutions in 48 countries were supplied with live colonies on all continents except Antarctica. There is some evidence linking exports and scientific studies with invasive populations, but others appear to be linked to secondary distributors of this species

Habitat characteristics influence the breeding of Rose’s dwarf mountain toadlet Capensibufo rosei (Anura: Bufonidae)

Direct anthropogenic factors (e.g., habitat loss, fragmentation, and degradation) threaten many amphibian populations, however some declines have occurred in supposedly pristine environments with no obvious causes. These enigmatic declines may be due to shifts in environmental factors influencing development and ultimately adult survival. Rose’s mountain toadlet Capensibufo rosei has undergone such an enigmatic decline, with several populations presumed to be locally extinct at historic breeding sites. The two remaining breeding sites (Silvermine (SILV) and Cape of Good Hope (CGH)) on the Cape Peninsula of South Africa were monitored for three years (2012-2014) for life history traits and ecological requirements. Males congregate at ephemeral pools during the middle of the austral winter, with females arriving to lay eggs and then immediately leaving. Breeding only occurs in a few of the available pools. We hypothesised that larval development in colder, deeper pools would result in smaller-bodied tadpoles, and ultimately in relatively smaller adults. Pools at SILV were significantly deeper and colder compared to CGH, with breeding occurring in pools that were 27.05±10.21 mm and 21.55±6.95 mm deep at SILV and CGH, respectively. Contrary to expectations, breeding adults and developing tadpoles at SILV were larger than CGH individuals. The percentage of non-developing eggs at CGH was high compared to SILV and other anuran species. Development within this threatened species may be influenced by pool characteristics, which could provide clues as to the factors that influenced local extinctions in historical populations

The structure of the littoral: effects of waterlily density and perch predation on sediment and plant-associated macroinvertebrate communities

1. Littoral zones are complex and important for mechanisms that maintain clear water and submerged plant dominance in lakes. Details of their structure are scarce, largely because sweep or grab sampling, the most commonly used approach, is unable to reveal much subtlety. 2. Invertebrate communities of plankton and sedimentary benthos, and of those living on submerged and floating leaves and their petioles of Nuphar lutea, were separately sampled from 2-m² mesocosms in a shallow lake, with different lily densities in the absence or presence of perch (Perca fluviatilis). 3. Increasing plant density led to reduced sedimentary benthos populations other than those of tubificids. This was ascribed to greater shading of algal producers on the surface sediment by the increasing leaf canopy. 4. Increasing leaf canopy increased the populations of several plant-associated taxa, suggesting that habitat availability was potentially limiting for these. 5. Submerged leaves supported more invertebrates per unit area than submerged petioles or the undersides of floating leaves. Greater periphyton production on leaf surfaces that had thinner cuticles and less waxy surfaces was probably responsible. 6. Perch predation had unexpectedly little effect, although the perch fed widely among the subhabitats, and fish population densities were relatively high. Predation was most intense on the planktonic and sedimentary benthos communities, especially on actively motile invertebrates such as isopods and amphipods. Macroinvertebrates associated with plant surfaces, not least the predominant Acroloxus lacustris, were relatively immune. There were more predator effects on submerged leaves than on floating leaves and their petioles. 7. Perch fed less effectively on some taxa at naturally high plant densities than at low and medium densities, and overall, the littoral communities showed resilience to fish predation, probably through the complexity of the plant structure

A general framework for animal density estimation from acoustic detections across a fixed microphone array

Funding for the frog survey was received from the National Geographic Society/Waitt Grants Program (No. W184-11). The EPSRC and NERC helped to fund this research through a PhD grant (No. EP/I000917/1).1. Acoustic monitoring can be an efficient, cheap, non-invasive alternative to physical trapping of individuals. Spatially explicit capture-recapture (SECR) methods have been proposed to estimate calling animal abundance and density from data collected by a fixed array of microphones. However, these methods make some assumptions that are unlikely to hold in many situations, and the consequences of violating these are yet to be investigated. 2. We generalize existing acoustic SECR methodology, enabling these methods to be used in a much wider variety of situations. We incorporate time-of-arrival (TOA) data collected by the microphone array, increasing the precision of calling animal density estimates. We use our method to estimate calling male density of the Cape Peninsula Moss Frog Arthroleptella lightfooti. 3. Our method gives rise to an estimator of calling animal density that has negligible bias, and 95% confidence intervals with appropriate coverage. We show that using TOA information can substantially improve estimate precision. 4. Our analysis of the A. lightfooti data provides the first statistically rigorous estimate of calling male density for an anuran population using a microphone array. This method fills a methodological gap in the monitoring of frog populations and is applicable to acoustic monitoring of other species that call or vocalize.PostprintPeer reviewe

Cyclic variation of the oviduct structure of Boulengerula taitana, an oviparous species of Gymnophiona: morphological changes, proliferation and apoptosis

Functioning of the amphibian oviduct is the subject of many studies, but detailed understanding of caecilian reproduction exists for very few species. In this study, a description is made of morphological changes of the oviduct of the caecilian Boulengerula taitana throughout the year, using conventional histology and immunohistochemistry. The reproductive cycle of this little-known species, originating from the Taita Hills in southeast Kenya, is annual. During the reproductive period (November–February), both lamina propria and the epithelium of the oviduct exhibit a maximum degree of development. The epithelial mucosa is more secretory and the cilia cells are abundant. Histological analysis shows the distribution of the different type of cells according to a specific pattern in the pars recta, pars convoluta and pars utera. Evaluation of proliferative (Ki-67 positive cells) and apoptotic cells (TUNEL and Apostain assays) into the different tissues brings out cyclic modifications of the lamina propria and epithelial cells throughout a seasonal cycle. The results demonstrate that the balance between cell proliferation and apoptosis reflects the functionality of the oviduct during the sexual cycle

Meteterakis saotomensis n. sp. (Nematoda: Heterakidae) from Schistometopum thomense (Bocage) (Gymnophiona: Dermophiidae) on Sao Tome Island

Meteterakis saotomensis n. sp. is described from Schistometopum thomense (Bocage), a gymnophionan endemic to the oceanic island of Sao Tome´ in the Gulf of Guinea. The specimens were assigned to Meteterakis Karve, 1930, based on the possession of a head with three rounded lips, not set-off from the body, the absence of interlabia and cordons, females with a long vagina and males with a preanal sucker, surrounded by a cuticularised rim and caudal alae that are supported by fleshy papillae. The new species is characterised by: body length 4.2–4.5 mm (males) and 5.1–6.4 mm (females); total length of oesophagus, including pharyngeal portion and oesophageal bulb, 820–856 μm (males) and 898–1,070 μm (females); length of pharynx 57–58 μm (males) and 65–68 μm (females); spicules equal, 410–521 μm long, with tessellated ornamentation throughout their length and alae, and with bevelled tip; gubernaculum or ‘gubernacular mass’ absent; tail length 164–176 μm (males) and 214–239 μm (females), with elongated tip; vulva at 2.3–2.8mmfrom anterior end, with anterior lip forming small flap. This is the second species of Meteterakis reported from gymnophionan hosts and the first from the Afrotropical region. Selected comparative morphological data for Meteterakis spp. are presented, and data on host range and geographic distribution are updated. The name M. striaturus Oshmarin & Demshin, 1972 is corrected to M. striatura to reflect the female gender of the genus name