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The past failure of large-scale, rural development in Amazonia has emphasized the value of small-scale, swidden-fallow management practices. The management strategies used by indigenous cultivators are well-documented, but few studies have examined how absorption by market-based economies may affect the economic and ecological stability of the agricultural system. In this study, we provide a detailed account ecological swidden-fallow management as it is practiced at Las Palmeras, Amazonas, Colombia; moreover, we assessed the effect of a shift from subsistence to market-directed production. A total of 68 species were selectively managed in the swidden/fallow system. Seventy-seven Percent of species at the site were managed for subsistence only, 22% were managed with a view to selling surplus at market. Only one species, Cedrela odorata, was managed solely for market production. A shift from subsistence-based to market-directed production may lower the ecological and economic stability of the system at Las Palmeras. Nonperishable production strategies, such as for timber production, appear to provide the most secure approach toward market, integration.

Abstract To evaluate the potential contribution of captive breeding to the conservation of exploited migratory Asian houbara Chlamydotis macqueenii , we estimated release numbers required to stabilise a population in a hunting concession (14,300 km2), under scenarios of local licensed hunting and flyway-scale protection. We developed a population model, initially 2350 adult females, re-sampling parameters measured through fieldwork and satellite telemetry, over 1000 iterations. With current flyway-scale unregulated harvest, and without any licensed hunting in the concession, populations declined at 9.4% year−1 (95% CI: −18.9 to 0% year−1); in this scenario a precautionary approach (85% probability λ ≥ 1.0) to population stabilisation required releasing 3100 captive-bred females year−1 (131% of initial wild numbers). A precautionary approach to sustainable hunting of 100 females year−1 required releasing 3600 females year−1 (153% of initial wild numbers); but if interventions reduced flyway-scale hunting/trapping mortality by 60% or 80%, sustaining this quota required releasing 900 or 400 females year−1, 38% and 17% of initial wild numbers, respectively. Parameter uncertainty increased precautionary numbers for release, but even with reduced precaution (50% probability λ ≥ 1.0), sustainable hunting of 100 females year−1 required annual releases of 2200 females (94% wild) without other measures, but 300 (13%) or no (0%) females under scenarios of a 60% or 80% reduction in flyway-scale hunting/trapping. Captive breeding cannot alone sustain migrant populations of wild C. macqueenii because it risks replacement and domestication. Trade and exploitation must be restricted to avoid either extinction or domestication. For exploited populations, supplementation by captive breeding should be used with caution. Highlights • Informs international, transboundary management of IUCN Vulnerable species • Evaluates strategy of stabilising exploited population by captive-bred releases • Demographic model parameterised by extensive fieldwork and satellite telemetry • Management solely through captive breeding risks domestication and replacement • Shows stabilisation requires controlling of hunting on flyway [ABSTRACT FROM AUTHOR]

Abstract: Understanding the composition and dynamics of soil seedbanks beneath mature conifer plantations is important for managing biodiversity in rotational forestry systems and in the restoration of former communities following the removal of tree crops. We examined the role of the buried seedbank in vegetation development after clear-felling of stands within coniferous plantation forest in eastern England. The buried seedbank of 29 mature stands planted in the early to mid 20th century on lowland heathland and marginal arable was determined by germination of seeds from soil cores (30 bulked cores per stand). Seedbank density was highly variable, with a mean of 3950 (S.D.±2400)seedsm−2. Ninety-eight species germinated, of which 37 were present in the surface vegetation of the mature stands; these 37 species had a higher density of seeds than the 61 species absent from the surface vegetation. Of those 61 species, 21 were recorded in the surface vegetation of recently replanted stands, suggesting that the seedbank may increase the plant diversity of replanted stands following clear-felling. The seedbank of mature stands was dominated by Urtica dioica and Holcus lanatus. Comparison of seeds in the top 20cm of soil between four paired mature and replanted stands showed felling and cultivation prior to replanting had little effect on either the density of the buried seedbank or the vertical seed density profile. Twenty-nine of the species recorded in the buried seedbank of mature stands were characteristic of heathland assemblages of the region, but were present at low densities. Notably, a number of perennial grass species characteristic of heathland were absent, while Calluna vulgaris occurred in the seedbank of few stands and then at low density. The potential for grass-heath restoration following clear-felling of first rotation conifer stands investigated in this study is likely to be low. [Copyright &y& Elsevier]

Abstract: Introduced Chinese muntjac Muntiacus reevesi are increasing in numbers and range within England and are colonising habitats occupied by native roe deer. Effective management of impacts requires knowledge of deer numbers and habitat associations. Few published estimates of muntjac numbers exist and habitat associations of this species are poorly known. Numbers of both muntjac and roe deer were estimated in 185km2 of lowland pine forest in eastern England, by standing crop pellet-group counts conducted in 217 plantation stands in February–March 2002. Estimated population density of muntjac (mean±95% CI: 64±13km−2) exceeded that of roe deer (28±6km−2), giving forest population estimates of 11,900±2370 and 5200±1070, respectively. Sensitivity analysis incorporating different published values of defaecation rate of each species, gave mean density estimates ranging from 59 to 76 muntjac km−2 and 25 to 33 roe deer km−2. The introduced species outnumber native roe deer two- to three-fold in this landscape. For both species, estimated numbers were approximately double subjective population assessments from deer managers, based on frequency of sightings. Both species attained high densities in pre-thicket and mature stands and used open re-stocked stands (aged 0–4 years) less than other growth stages. Muntjac also occurred at substantial densities in thicket and pole stages. Roe deer aggregated on bramble across all habitats, while muntjac were positively associated with bramble in older stands (≥25 years). The two species showed substantial overlap in their use of growth stages (Pianka''s index of overlap, O =0. 93) and individual stands (O =0.63). This supports proposals that inter-specific competition may occur between these two species. At a landscape scale, muntjac density was higher in forest blocks with a greater ratio of open habitat perimeter to forest area; roe deer did not show this relationship. For both species, pellet-groups disappeared much faster than published estimates of decay rates previously used in designing pellet accumulation studies. [Copyright &y& Elsevier]

In parts of England areas of woodland previously coppiced are being brought back into active coppice management at a time when deer populations are increasing, and after decades with an absence of management. This paper examines the effects of overstorey canopy cover, coppice restoration, and deer browsing on the growth, and structure of the coppice and other understorey vegetation. At 11 coppice woodlands in lowland England, coppice compartments were categorised based on their coppicing history (restored versus continuous), low and high overstorey canopy cover, and low and high deer browsing levels. Gross vegetation structure in the years following harvesting was also examined. Deer browsing was assessed from signs of structural browsing damage and presence of deer. Deer browsing and overstorey cover reduced the density of the understorey. There was also a weak effect of coppice history with restored coppice exhibiting less vigorous vegetation than continuous coppice. Deer browsing damage was more pronounced in compartments with a low overstorey canopy cover, possibly due to the more luxuriant understorey coppice re-growth. Browsing damage is consistent with that expected at low to moderate levels of potential browsing intensity. Future restoration of coppice and growth of stools after coppicing is likely to be successful and worthwhile only if active measures are taken to reduce deer browsing damage and possibly deer populations as a whole. [Copyright &y& Elsevier]

Understanding deer habitat use is important in predictive management of increasing deer populations and in assessing the potential for inter-specific competition, particularly between native and introduced species. Habitat usage by roe deer and introduced Chinese muntjac was studied in a 1200 ha study area within Thetford Forest, a commercially managed coniferous forest in Eastern England. Habitat use was related to forest growth stage and vegetation composition by pellet-group clearance transects conducted every 2 months from March 2000 to March 2001. Higher densities of roe deer were found in young plantations, while muntjac numbers were lower in open restocks and grassy areas and higher in older stands and areas with greater cover of bramble Rubus fruticosa agg. Overall, muntjac showed greater habitat selectivity than roe deer. The overlap between the two species in use of individual stands (single, even-aged management compartments) was significantly lower than overlap in use of growth stages (consisting of many individual stands), suggesting ecological partitioning at finer spatial scales. However, overlap in habitat use as measured by Pianka’s index remained substantial at both scales (mean 0.40±0.16 S.D. for stands and 0.55±0.11 for growth stages). Habitat overlap was greatest in winter when both species aggregate on bramble. There is, therefore, potential for exploitation competition in the event of food scarcity. [Copyright &y& Elsevier]