Amphibian Conservation

This comprehensive British synopsis was prepared with funding by Synchronicity Earth and Aria. It is the fourth volume in the Synopses of Conservation Evidence series and is linked to the online www.conservation evidence.com where the full text is available without charge as an alternative to paying for it in print. Its dense text summarizes and discusses selected world studies concerned with the results, positive and negative, of tampering with natural populations. These have been usually well-meaning attempts to compensate for the damage done by expanding human populations. Impacts may have been either direct by past eradication of individuals or indirect through destruction or alteration of habitats critical to the survival of one or more amphibian species.

The introduction stresses that this survey is intended to influence those in a position to make decisions that could save biodiversity one case at a time. Al though recommendations are not provided, basic ecology is included. Interventions that are discussed are not ranked by importance or extent of their effects or evaluated by their quality. The multitudes of references to publications of many countries are grouped with the headings where they are appropriate.

The text is broken into 14 sections each with key messages and various subheadings. Ten concentrate on threats: residential and commercial development (interventions specific to development); agriculture (engage farmers and other volunteers, terrestrial and aquatic habitat management); energy production and mining (mist habitat); transportation and service corridors (install culverts or tunnels, barrier fencing, modify drains and kerbs, signs and road closures, assistance during migration); human intrusions and disturbance (signs and access restriction); natural system modifications (prescribed fire, herbicides, mechanical removal of vegetation, regulate water levels); invasive alien and other problematic species (reduce predation, competition and habitat alteration by other species, reduce parasitism and disease by chytridiomycosis and ranaviruses); pollution (agricultural and industrial); climate change and severe weather (irrigation, ephemeral ponds, shelter habitat, gradients). These are followed by habitat protection (connectivity, buffer zones); habitat restoration and creation (terrestrial, aquatic); species management (translocate, captive breeding, rearing, release); education and awareness raising (campaigns, programs, citizen science).

A 17-page index concludes the book but is a disappointment. Canadian studies are not cited by country or province forcing the reader to search through the text for references to them. However, there are entries for other countries and many entries by species.

This is part of an ambitious series that aims toward accumulating a comprehensive summary of evidence on the effects of conservation interventions on saving the diversity of life over the entire planet. Among other titles completed is Bee, Bird, Farmland and more are being prepared to cover different groups and habitats.

-- Francis R. Cook * The Canadian Field Naturalist *

Nature management for amphibians based on scientific research is rare in practice. Field workers read little, especially literature which is not in their mother-tongue, and readily assume they know what to do based on their experience. This book collects all relevant literature regarding amphibian management and shows what interventions have a real effect and to what extent, but also includes those about which knowledge is still lacking. The book is organised in a practical fashion and gives a detailed overview of all possible interventions and their relevance. Topics are divided in an orderly fashion with separate entries for types of threat, for approaches from the habitat or species concept, and for educational purposes. This set-up makes the book exceptionally well-suited to the realities of nature management. It does not provide recipes for what exactly to do, but does offer the reader the option of choosing certain interventions based on proven efficacy.

An example might clarify the book's contents. The construction of new pools is described in detail, and is supported by results from 28 studies. These have been divided into their effects on amphibians generally, into comparisons with natural pools with regards to numbers and species composition, into the success rates of colonisation and population stability, and into factors influencing reproductive success. After that the information is further divided into effects on species and species groups. Based on all this information readers can determine for themselves whether planned interventions can be expected to lead to the desired outcome.

The book's contents are also accessible online via www.conservationevidence.com, where it can be downloaded or read online. Similar books have been published on, amongst others, bats, birds, and bees.

This book clearly brings us a large step closer to making the right choices in practical nature management, and is indispensable for those involved in doing so.

-- Tom Stumpel * RAVON *

The book begins with six pages briefly describing the methods the authors used to identify and locate published studies, and to systematically quantify their results. The authors summarize evidence for nine threats (Residential and Commercial Development, Agriculture, Energy Production and Mining, Transportation and Service Corridors, Human Disturbances, Habitat Modification, Invasive Species, Pollution, and Climate Change) and four solutions (Habitat Protection, Habitat Restoration, Species Management, and Education and Outreach). All topics are focused on practical hands-on actions; the book does not reference any modeling studies, does not address policy efforts, and does not discuss ethical considerations. The book would have benefitted from a summary chapter that gave an overview of success for each topic and taxonomic group. Skimming through the extensive examples, I concluded that we have had inconsistent results in our interventions to conserve amphibians, despite varied approaches in numerous systems. It was sobering to realize that even habitat protection efforts—considered as close to a sure thing as we get in conservation—are often not assessed, and are only partially successful.

To demonstrate how the book is organized, I summarize the chytridiomycosis abatement strategies, listed under the Invasive Species section. This section included eleven actions that attempted to reduce chytridiomycosis: two reducing geographic spread, three reducing amount of Bd in the environment, and six reducing infection load on amphibians. The authors provided (a) a short overview, (b) a statement of reported successes, (c) a brief background summary, (d) a few pages of text describing each article’s findings, and (e) references. It would have been nice if the authors included some sort of gap analysis identifying actions that have not been tested. I thought readers would have benefited if the authors provided details on the original causes of declines, what kind of effort went into finding unreported and unpublished failures, and whether interventions were designed to address those original threats or were only able to assess net changes. It would also be helpful if the authors discussed whether effective interventions would likely work for other species or in other areas. As in most cases in conservation biology, the devil is in the details, and because many of the details are not included, it’s hard to assess the assessment.

A good example of the importance of details is the section on Species Management. In this section, two approaches are described: translocations and ex-situ conservation (e.g., captive breeding, rearing, and releases). Translocations are organized by taxonomic group (i.e., frogs, toads, salamanders), which shows the incredibly small number of such studies and the bias towards three species: Wood Frogs (Lithobates sylvaticus), Natterjack Toads (Epidalea calamita), and Great Crested Newts (Triturus cristatus). Success was qualified by the type of persistence, the length of persistence, and the percent of attempts that persisted for some amount of time; only one study mentioned that a population was self-sustaining. The authors use the original study to define success rather than adopting a universal definition. Consequently, projects that they identify as successful may not actually result in self-sustaining populations. Sections on captive breeding and release are also organized into sections on frogs, toads, and salamanders with most studies conducted on three other species: midwife toads (Alytes spp.), harlequin frogs (Atelopus spp.), and Green and Golden Bell Frogs (Litoria aurea). Here’s where I’d want to know what the original threats were that led to captive breeding and also what has been done, but not published. For example, in the case of the harlequin frogs, we know they are in captivity because of chytridiomycosis, but the book does not mention this. Do they breed in captivity? Yes! Is it a success? Well, maybe. We don’t really know how many Atelopus species were brought in to create captive assurance colonies but failed and were never reported in the literature, or even the degree to which the facility tried to establish large captive populations. We also don’t know why they failed; there are many practical reasons why organizations do not even attempt to breed their frogs (limited space, time, funding, interest). Negative results, details on causes of failure (lack of knowledge, resources, patience, policies), and what the stated objectives of holding captive assurance colonies were are what we need to determine effectiveness. The details of how we define success are critical to assessing the efficacy of our conservation efforts, and those details are glossed over here.

In terms of mechanics, the writing is simple, straightforward, and factual, but not especially engaging, as it avoids any personal ideas or synthesis statements, focusing instead on reproducing the original information. I found few errors in the sections I read and the presentation was balanced and uncontroversial. The layout is not especially attractive as the book completely lacks images, graphics, tables, figures, and color. The book also uses small fonts, and many styles and formats of headings and subheadings, but without figures or tables to break up the text, I found it easy to get lost. A more serious complaint is the lack of a combined literature cited for the whole book.

This book and online journal will be excellent resources for those looking to get up to speed on what actions have been attempted to conserve amphibians and the outcomes of those efforts. It will be a valuable guide for graduate students interested in evaluating evidence for effective amphibian conservation, and is sure to generate new approaches, critical analyses, and discussions. The free online version makes this especially valuable for conservation practitioners and students from all countries, and should facilitate real-time updates as new studies are published. More than anything, this book reveals the surprisingly large number of species, regions, and threats that have yet to be tested, the need for critical assessment and discussion of “success,” and a realization of how much work we have to do.

-- Karen R. Lips * Copeia *

This book attempts to summarize all of the published evidence relating to conservation interventions aimed at amphibians and specifically, where interventions have been quantitatively monitored. This ranges from very small specific interventions such as the introduction of artificial hibernacula to wide ranging interventions such as the Million Ponds Project in the UK. No attempt is made to make recommendations, merely to lay out the evidence in an easy to read and easy to find format in a way that can help decision makers at a local, national or international scale make more informed judgements as to the most effective measures to implement. The first half of the book is arranged into chapters that each relate to a specific threat such as climate change, transport networks, agriculture and pollution whilst the second half examines the impact of habitat management, species management (captive breeding and translocations) and education and awareness raising.

One of the big plus points of this book is that it is very easy to establish if there is evidence available about a particular subject and where to find the source material. In this respect it serves its purpose well. However, it is intriguing to examine whether the book can actually be applied by land managers or those giving advice to land managers to fine tune the management of sites for their amphibian populations. The Kent Reptile and Amphibian Group regularly gives advice to a wide range of organisations and individuals about managing ponds and terrestrial habitat for amphibians and most of the advice is based around generally accepted best practice guidance. At least 90% of advice is covered by just a few basic principles. In other words, creating ponds is good, and almost always more cost effective than managing existing ponds, discouraging birds and fish is useful, maintaining structurally complex terrestrial habitat will help and not moving the widespread amphibians around except under exceptional circumstances is the best option. So, could this book confirm that this is sound advice based on well established, published literature or just the ramblings of well meaning amateurs that is at best ineffective or in a worst case scenario, counterproductive?

Things started well, pond creation gets a resounding thumbs up though the success of specific species depends upon the kind of ponds created and some studies have expressed doubt that the creation of ponds specifically for translocated species leads to self-sustaining populations. In contrast, evidence suggests that pond restoration can have mixed effects on existing amphibian populations. Fish control similarly has good evidence to back up its effectiveness though the use of piscicides can also kill off amphibian populations. The evidence to support other interventions is less conclusive as the example of excluding waterfowl shows. The book simply states that ‘We captured no evidence for the effects of preventing heavy usage or excluding wildfowl from aquatic habitat on amphibian populations.’ Herein lays the challenge of writing a book such as this. The complexities of amphibian habitat management and the impact of interventions on a range of species m