Katarzyna Nowak

Bolder Thinking for Conservation

SHOULD CONSERVATION TARGETS, such as the proportion of a region to be placed in protected areas, be socially acceptable from the start? Or should they be based unapologetically on the best available science and expert opinion, then address issues of practicality later? Such questions strike to the philosophical core of conservation. Ambitious targets are often considered radical and value laden, whereas modest targets are ostensibly more objective and reasonable. The personal values of experts are impossible to escape in either case. Conservation professionals of a biocentric bent might indeed err on the side of protecting too much. Anthropocentric bias, however, more commonly affects target setting. The pro-growth norms of global society foster timidity among conservation professionals, steering them toward conformity with the global economic agenda and away from acknowledging what is ultimately needed to sustain life on Earth.

Elephants, ivory, and trade.

Trade decisions made by the Convention on International Trade in Endangered Species must place science over politics. Tanzania and Zambia are petitioning the Convention on International Trade in Endangered Species (CITES) to “downlist” the conservation status of their elephants to allow sale of stockpiled ivory. But just 2 years after CITES placed a 9-year moratorium on future ivory sales (1), elephant poaching is on the rise. The petitioning countries are major sources and conduits of Africas illegal ivory (2–4). The petitions highlight the controversy surrounding ivory trade (5) and broader issues underlying CITES trade decisions.

Over-diagnosis of malaria by microscopy in the Kilombero Valley, Southern Tanzania: an evaluation of the utility and cost-effectiveness of rapid diagnostic tests

BackgroundEarly and accurate diagnosis of febrile patients is essential to treat uncomplicated malaria cases properly, prevent severe malaria, and avert unnecessary anti-malarial treatments. Improper use of anti-malarials increases the risk of adverse drug reaction and the evolution of drug/parasite resistance. While microscopy is the most common form of malaria diagnosis, concerns over its accuracy have prompted the incorporation of malaria rapid diagnostic tests (RDTs) into many national malaria control programmes.MethodsOver a three-month period, a direct comparison between microscopy and RDTs was made in a rural, private dispensary in the Kilombero Valley, Morogoro District, southern Tanzania, with the aim of estimating the extent of malaria over-diagnosis and over-treatment with anti-malarials. The study cohort was made up of patients referred by the dispensary’s clinician for malaria testing. One hundred percent of patients approached agreed to participate in this study and were then tested using both microscopy and RDTs. Using the results from the comparison of the two tests at this dispensary, the potential cost effectiveness of introducing RDTs to a neighbouring public health centre was estimated on the basis of this centre’s past malaria records spanning December 2007 to August 2011.ResultsAt the private dispensary, the apparent prevalence of malaria was 78% based on microscopy whereas the true prevalence, calculated using RDTs as the gold standard, was estimated at 14%. This discrepancy indicates that when using microscopy as the sole diagnostic test, malaria is being over-diagnosed by approximately a factor of five in this setting. At the public clinic, apparent malaria prevalence based on microscopy was 74%. If similar rates of over-diagnosis are assumed, 5,285 patients of the 6,769 patients positively diagnosed with malaria using microscopy were likely given unnecessary anti-malarials, and their true cause of illness was not addressed. The introduction of RDTs to the public clinic would be highly cost-efficient, with an estimated net saving of over 96 USD/month.ConclusionsCompared with RDTs, microscopy led to almost four out of five patients being over-diagnosed with malaria in this rural part of Tanzania. A policy that encompasses both the private and public sectors of health care is needed to ensure quality diagnostic testing for febrile patients. With estimated prevalence at 14%, RDT introduction is recommended given WHO findings that RDTs are predicted to be cost-effective in prevalence areas of less than 20%. The use of RDTs in malaria diagnosis would not only reduce government spending but would prove beneficial to ensuring appropriate care and treatment of febrile illness.

Demographic Structure of Zanzibar Red Colobus Populations in Unprotected Coral Rag and Mangrove Forests

AsbtractMore than half of the global population of the endangered Zanzibar red colobus (Procolobus kirkii) live outside the single major protected area on Zanzibar Island. We present data on the 2 largest, discrete subpopulations living in unprotected areas at extremes of the species’ range. We compare the size and structure of 11 groups, specifically 6 core groups inhabiting interior, mature forest with 5 peripheral groups living in disturbed/degraded edge habitats. Groups living in southern mangrove forest—a species-poor but more productive and less seasonal habitat than coral rag thicket—had larger group sizes and more heterogeneous age structure, were more stable, and had higher rates of infant survival than did groups in northern coral rag. Group size ranged from 5.5 ± 1.6 SD (the smallest reported for this species) in edge coral rag to 31.2 + 1.9 SD in core mangroves. Edge groups were significantly smaller than core groups in northern coral rag while in the south, where all groups had access to mangroves, we found no significant difference in mean group size between edge and core areas. Groups using mangroves exhibited frequent social play, an indicator of habitat quality, and had a higher ratio of births per female per year. We suggest that mangroves are an important refuge and possibly source habitat for Zanzibar red colobus. We urge the conservation of mangrove and remaining coral rag in the unprotected areas described here in an effort to sustain this endemic species throughout its range.

“Specialist” Primates Can Be Flexible in Response to Habitat Alteration

An increasing number of field studies on behavioral adaptations and learning suggest that a capacity for flexibility in local responses to disturbance could buffer some so-called specialists against that disturbance. We discuss how specialization, rather than an intrinsic species trait, appears to be moderated by flexible and learned behavior and may not represent a useful trait in comparative analyses of extinction vulnerability. Furthermore, the use of primate species as indicators of the effects of disturbance on communities needs to be balanced with data on their capacity to adjust behaviorally. We present recent examples of innovative and flexible behavior in primate taxa, some of which have traditionally been viewed as highly specialized, for example species of red colobus. We also highlight research gaps in the ecological specialization–behavioral flexibility domain.

Status of Zanzibar Red Colobus and Sykes's Monkeys in Two Coastal Forests in 2005

Abstract: We censused two discrete subpopulations of the endangered Zanzibar red colobus (Procolobus kirkii) and sympatric Sykess monkeys (Cercopithecus mitis albogularis) between February 2004 and September 2005 in two coastal forests in Zanzibar, including the northernmost (Kiwengwa-Pongwe Forest) and some of the southernmost (Uzi and Vundwe Islands) extents of P. kirkiis range. Surveys totalled 365 hours and 307.8 km along >16 km of line transects; 472 sightings were made (Red colobus n = 252; Sykess monkey n = 220). The southern forests (coral rag with adjacent mangrove) of Uzi and Vundwe Islands were found to support P. kirkii at a higher estimated density (29.6 groups/km2) relative to the northern coral rag forest (lacking mangrove) in Kiwengwa-Pongwe (7.5 groups/km2). However, for red colobus in coral rag, up to c.40% of these “groups” could be “sub-groups” based on our observations of consistent fission-fusion and small groups seen during the census (6.63 ± 0.4SE in Kiwengwa, 6.64 ± 0.33SE in Uzi) and behavioral follows in this habitat type. We therefore also include density estimates expressed as individuals/km2 (49.72 individuals/km2 in Kiwengwa, 196.32 individuals/km2 in Uzi). On Uzi and Vundwe Islands, colobus densities were higher than those of Sykess monkey (Sykess monkey density = 18.9 groups/km2), while we found no difference between the density of these two taxa in Kiwengwa (Sykess monkey density = 8.1 groups/km2) where encounters with humans were more frequent, vegetation was more disturbed, and the two species often associated. Although these populations represented a fraction of the historical total population of red colobus and Sykess monkeys on Zanzibar, their estimated abundance was significant, and their marginal habitat and unprotected status were important in the general context of primate conservation in unprotected and fragmented landscapes.

Ivory crisis: Growing no-trade consensus

In their Perspective, “Breaking the deadlock on ivory” (15 December 2017, p. [1378][1]), D. Biggs et al. propose steps to enhance unity around the African elephant poaching crisis. We support their recommendations for dialogue among African elephant range states. However, the Perspective

Conservation Biology, Discipline of

The increasing size of the human ecological footprint will require a matching increase in conservation efforts if significant, viable communities of nonvoting species are to have any real chance of persisting in natural forms where they can evolve and provide vital services to the human economy, health, and wellbeing. Conservation biology, one of the fastest-growing and developing fields of modern scientific research is an applied, mission-driven discipline that integrates principles of natural and social sciences with the objective of ensuring the long-term persistence of biodiversity on Earth. Its origins were a direct reaction to the current biodiversity crisis. This article reviews current trends in conservation biology, using a hierarchical organization beginning from the largest level of ecosystems and communities to the intermediate level of species and populations, and down to the smallest level, that of individuals and genes. The authors highlight the increasing emphasis on maintaining “ecosystem services” and landscape-level processes, i.e., fully functioning ecosystems made up of interacting species, and increasingly view humans as part of the equation.