Recovery of understory bird movement in post-pasture Amazonia

I sought to understand how forest fragmentation and secondary growth affect avian movement at the Biological Dynamics of Forest Fragments Project (BDFFP) near Manaus, Brazil. When deforested areas are abandoned, secondary forests regenerate, allowing rainforest animals to gradually recovery their ability to use formerly inhospitable habitat. My colleagues and I captured 2773 understory birds of ten foraging guilds along the edges of primary forest fragments and variable secondary forest. Age of secondary forest along edges was the most important variable driving capture rates on primary/secondary edges. Mean recovery to pre-isolation capture rates was 26 years after abandonment, but terrestrial insectivores took far longer to recover than other guilds, ¡Ý 54 years. I radio-tracked 73 understory insectivores of three species in variable landscapes to uncover patterns in avian movement in secondary growth¡ªspecifically evaluating space use (home range, movement rate, etc.), edge responses and habitat transition probabilities. Space use varied widely as secondary growth recovered, with species showing vastly different spatiotemporal strategies in returning to forest. Woodcreepers Glyphorynchus spirurus and Xiphorhynchus pardalotus recovered to primary-forest-level edge responses and transition probabilities after 11¨C15 and 15¨C20 years, respectively. En route to recovery, both woodcreepers increased home range sizes and movement rates in young secondary forests. Formicarius colma, a common terrestrial insectivore, had a far more rigid strategy, avoiding young secondary forest, then using space in older secondary forest similarly to the way it used space in primary forest. With bird ages pooled, F. colma showed a return to no edge response about 28¨C30 years after land abandonment, with some evidence for an edge response by young birds even 27¨C31 years post-abandonment. Further, through habitat transition probabilities, I showed that F. colma preferred primary forest over 27¨C31 year-old secondary forest (the oldest at the BDFFP), indicating that even after 27¨C31 years, secondary forest had not recovered for movements of this terrestrial insectivore. By quantifying how land-use patterns affect avian movement, connectivity, and community dynamics, we will be generating the understanding necessary to manage heterogeneous landscapes for biodiversity conservation in the 21st century and beyond

Home Ranges of Rusty Blackbirds Breeding in Wetlands: How Much Would Buffers from Timber Harvest Protect Habitat?

We calculated the home ranges and core areas of 13 adult Rusty Blackbirds (Euphagus carolinus) in Maine to determine (1) the area requirements of breeding adults, (2) whether area requirements of the sexes and of colonial and noncolonial individuals differ, and (3) the proportion of the home range and core area that would be protected by a buffer of no logging of 50–100 m around occupied wetlands. Mean home ranges (37.5 ± 12.6 ha) and core areas (11.1 ± 2.8 ha) were large in comparison to those of other breeding icterids, and adults often foraged in multiple unconnected wetlands. Rusty Blackbirds that were part of a loose colony had home ranges and core areas three times larger than those of pairs that nested solitarily, which we speculate may be due to adults following one other to feed on unpredictable emergences of aquatic insects. Home ranges and core areas included a surprisingly small amount of wetland habitat, only 12% and 19% respectively, but adults often foraged in small wet patches (\u3c16 m2) in otherwise upland habitat. The 75-m buffers around wetlands that we recommended in a concurrent study may help protect the Rusty Blackbird\u27s nesting habitat, but such buffers contained less than half the average home range, suggesting that they may be of only limited benefit as a conservation strategy for protecting foraging habitat

Habitat occupancy of Rusty Blackbirds (Euphagus carolinus) breeding in northern New England, USA

The Rusty Blackbird (Euphagus carolinus), an uncommon songbird often associated with northern coniferous wetlands, has experienced a precipitous population decline since at least the early 20th century. Here, we provide the first analysis of breeding-habitat occupancy at the wetland scale and make recommendations for streamlined monitoring. We modeled occupancy and detectability as a function of site (i.e. habitat-based) and sampling (i.e. visit-specific) variables collected at 546 wetlands in northern New England, USA. Wetland occupancy (mean 6 SE ¼ 0.07 6 0.02 in randomly selected wetlands, and 0.12 6 0.02 in all wetlands surveyed) was best explained by variables describing Rusty Blackbird foraging habitat (PUDDLES: a proxy for shallow water), nesting habitat (coniferous adjacent uplands), and evidence of beavers. In contrast to Rusty Blackbirds’ selection of pole-stage conifers at the nest-site scale, stand age did not affect occupancy at the wetland scale. It appears that most wetlands in northern coniferous forest landscapes, regardless of stand age, offer dense conifer patches nearby and provide suitable breeding habitat if quality foraging sites (e.g., areas of shallow water) also are available. Detectability (0.29 6 0.04) decreased with increasing wind speed, and decreased about fourfold over the course of the breeding season. Rusty Blackbirds responded to broadcast of conspecific vocalizations by flying toward the observer and perching more often than prior to broadcast, demonstrating that broadcasts can be a useful tool to enhance visual detectability. Given our results, observers can now focus site selection on wetlands and sampling conditions most likely to maximize detections of Rusty Blackbirds

Moult of overwintering Wood Warblers <i>Phylloscopus sibilatrix</i> in an annual-cycle perspective

Wood Warblers, an Afro-Palearctic migrant species, are declining steadily in Europe likely due to mortality outside their breeding grounds. However, little is known about their overwintering, and records about the sensitive life-cycle stage of moult in Africa are practically absent. To fill this gap, we report on moult of Wood Warblers captured over two winters (January–February) in 2019–2020 in Cameroon. We caught 14 individuals, of which 12 were monitored for flight feather moult. All inspected individuals showed advanced stages of flight feather renewal. Despite low sample sizes, Underhill-Zucchini moult models aptly explained variation in primary and secondary moult (R2 = 0.61). Estimated moult onset date was 26 December, completion date was 25 February, and moult duration was 61 days. These findings fit well with experimental data on the annual cycle and the timing of recently published migration tracks of Wood Warblers. Jointly, the data suggest that moult timing is set by an internal programme, which enables Wood Warblers to organise their multi-stage migration such that they reach suitable moulting habitat in time, and can depart in time with a fresh plumage for the breeding grounds. In our study, moult occurred during the peak of the dry season, which in Cameroon nonetheless shows high relative humidity. During our mist-netting on 28 cocoa plantations of varying shade cover, Wood Warblers were caught on 6 farms whose canopies were comparatively open. These data suggest that the birds encounter in Cameroon relatively stable climatic conditions for moult, and do not measurably prefer closed-canopy forests. Our findings are important, because successful moult increases survival prospects and because moult needs to be safely embedded in a migratory life cycle. Hence, information on moult timing and location is essential for identifying year-round vulnerabilities of Wood Warblers.<br/

Nest-Site Selection and Nest Survival of the Rusty Blackbird: Does Timber Management Adjacent to Wetlands Create Ecological Traps?

Animals are subject to ecological traps when anthropogenic changes create habitat that appears suitable but when selected results in decreased fitness. The Rusty Blackbird (Euphagus carolinus) breeds in boreal wetlands and has declined by 85–95% over the last half century. We studied nest-site selection and daily nest survival rate (DSR) of 43 Rusty Blackbird nests in northern New England and evaluated whether regenerating logged areas adjacent to wetlands created ecological traps. Although nesting adults avoided high-canopied forests and selected areas with dense balsam fir (Abies balasmea) 1 to 3 m high, those characteristics were not associated with DSR. Conversely, the frequency of speckled alder (Alnus incana) and sedges (Cyperaceae) in the nest plot varied with DSR, suggesting that the risk of predation of nests within wetlands was lower. DSR also varied with past logging; nests in plots not harvested recently were 2.3x more likely to fledge young than nests in plots harvested within 20 years. When logging extends to the edges of or into wetlands, the subsequent dense regenerating conifers appear to attract Rusty Blackbirds to nest closer to or within these human-altered uplands, exposing their nests to increased predation not typical of unaltered wetlands. Three surrogates for habitat preference did not differ by timber-management history, suggesting that the birds do not prefer habitats that increase their fitness. Rusty Blackbirds nesting in harvested wetlands may be subject to “equal preference” ecological traps, and we suggest that buffers 75 m wide around the perimeter of suitable wetlands should increase DSR

Ecology and conservation of avian insectivores of the rainforest understory: A pantropical perspective

Avian insectivores of the tropical rainforest understory ("understory insectivores") are common, diverse, and often sensitive to disturbance of tropical forest, making them useful as sentinels of rainforest ecosystem change. At the 2013 joint American Ornithologists' Union and Cooper Ornithological Society meeting in Chicago, USA, researchers convened a symposium to address the ecology and conservation of understory insectivores. This Special Issue of Biological Conservation is the result of that symposium: a collection of articles that unites our efforts to further understand and conserve understory insectivores. In this introductory paper, we review the diversity and ecology of understory insectivores, identify threats to the guild, discuss hypotheses on drivers of population declines, and make suggestions for future research. Deforestation and forest degradation are the immediate threats to this guild, with agricultural expansion (particularly oil palm plantations), urbanization, road expansion and logging leading the list. Although vulnerabilities of this guild are most evident in the Neotropics, there are few studies from Asia and fewer still from Africa-we recommend increased geographic coverage. If we are to understand the vulnerabilities of understory insectivores from a pantropical perspective, researchers should prioritize understanding the most serious threats (e.g., edge effects, deforestation, fragmentation, etc.) and standardize efforts to gauge understory insectivores' response to these threats (e.g., via species richness, abundance, demographic metrics). A coordinated approach by researchers working in tropical rainforests across the globe can help us understand the ecology of understory insectivores and meaningfully apply conservation and management actions. © 2015

Fewer pests and more ecosystem service‐providing arthropods in shady African cocoa farms: Insights from a data integration study

Agricultural intensification is leading to conversion of cocoa agroforestry towards monocultures across the tropics. In the context of cocoa agriculture, arthropods provide a range of ecosystem services and dis‐services. Arthropod pests (e.g., mirids and mealybugs) can cause major damage to crops, whilst pollinators and natural enemies (e.g., predatory insects and parasitoids) have the potential to enhance agricultural yields. Understanding how intensification of cocoa farming affects different arthropod groups is therefore important in maximising the abundance of beneficial arthropod taxa and reducing pest burdens. However, little is known about the influences of agricultural intensification on tropical arthropod communities, especially in Africa, where ~70% of the world's cocoa is produced. Most research on arthropod communities considers data from different sampling methods separately, as proxies of abundance; whilst these proxies can be informative, estimating true abundance enables direct comparison between arthropod taxa, and therefore the study of community dynamics. Here, we develop a Bayesian hierarchical model that integrates data from three common arthropod survey techniques to estimate population size of arthropod orders and to investigate how arthropod community composition responds to farm shade cover (an indicator of management intensity). Our results show that eight of 11 arthropod taxa responded to farm shade cover; importantly, brown capsids (the primary pest of cocoa in Africa), Coleoptera pests and Hemiptera pests decreased with increasing farm shade cover, whilst Araneae (natural enemies) and Diptera (potential pollinators) were more abundant in shady farms. Synthesis and applications. To achieve lower pest burdens and higher abundances of potential pollinators and natural enemies, African cocoa farms should maintain a dense canopy of shade trees. The current shift towards high‐intensity cocoa farming in Africa could result in long‐term losses due to pest infestations and loss of arthropod‐mediated ecosystem services

Not all farms are created equal: Shady African cocoa farms promote a richer bat fauna

Bats provide important pest suppression services with economic value to cocoa farmers, yet the impact of cocoa farm management on bat diversity metrics is still poorly understood. This is especially important if we consider that Afrotropical cocoa farms supply 68 % of the world's chocolate market, with expected increases in production in the forthcoming decades. In this study, we investigated for the first time how bat abundance, richness and diversity varied between African cocoa farms with different levels of shade tree cover, shade tree communities and cocoa characteristics. We found that shade tree cover and shade tree height were the main drivers associated with an increase of Shannon diversity, and abundance and richness of insectivores. Frugivorous and nectarivorous bats were positively associated with the presence of planted shade trees, but richness varied with the size of shade trees. The insectivorous Hipposideros fuliginosus was only present in high shade farms, being captured 51 times only in this shade system, while the frugivorous Myonycteris angolensis was associated with low shade farms. Our findings show that indeed not all farms are created equal, with high shade farms with large, tall forest shade trees (i.e., containing key plant resources) having richer bat communities. Therefore, policymakers seeking to conserve wildlife within cocoa farming systems should adopt cocoa management systems like those mentioned above and promote a combination of forest and planted shade trees to be able support a rich community of insectivorous, frugivorous and nectarivorous bats and maintain their associated ecosystems services

Evaluating a new generation of wearable high-density diffuse optical tomography (HD-DOT) technology via retinotopic mapping in the adult brain

We investigated the performance of a novel HD-DOT system by replicating a series of classic visual stimulation paradigms. Haemodynamic response functions and cortical activation maps replicated the results obtained with larger fibre-based systems

High-dose imatinib in newly diagnosed chronic-phase chronic myeloid leukemia: High rates of rapid cytogenetic and molecular responses

Purpose: Long-term clinical outcome data have established imatinib 400 mg/d as standard front-line treatment for newly diagnosed patients with chronic myeloid leukemia (CML). Patients and Methods: The Rationale and Insight for Gleevec High-Dose Therapy (RIGHT) trial is a multicenter study of imatinib 400 mg twice a day as initial therapy in 115 patients (70% Sokal low risk) with newly diagnosed CML in chronic phase who were observed for both molecular and cytogenetic responses for up to 18 months. Eighty-three patients (72%) completed the study, 10 patients (9%) discontinued the study because of adverse events, and six patients (5%) discontinued because of unsatisfactory therapeutic effect. Results: Polymerase chain reaction analysis demonstrated rapid kinetics of major molecular response (MMR), with 48% of patients achieving MMR by 6 months, 54% by 12 months, and 63% by 18 months. Corresponding complete molecular response rates were 39%, 44%, and 55%, respec- tively. Median dose-intensity was 98%. Overall, 79% of patients who received at least 90% dose-intensity achieved MMR. The most frequent adverse events included myelosuppression, rash, fatigue, and musculoskeletal symptoms. Conclusion: This study suggests that imatinib 400 mg twice a day results in more rapid reduction in tumor burden than imatinib 400 mg/d with minimal added toxicit