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Fires are an ecological process essential for species dependent on early successional habitat in forested landscapes. In a wildlife context, clearcut forestry practices can mimic forest fires through the creation of early successional forest clearings, however, evidence that clearcuts provide the same ecological value as fire is mixed. In temperate deciduous/hardwood forests, many species that depend on early successional habitat are known to use clearcuts, including Eastern Whip-poor-wills ( Antrostomus vociferous ) and Common Nighthawks ( Chordeiles minor ), two threatened aerial insectivorous birds. However, the relative importance of recent clearcuts as breeding habitat relative to other more naturally open habitat types in the boreal forest is unknown. In May-July 2015 we studied occupancy and detectability of these two species in the boreal forest of northwestern Ontario. We first determined whether occupancy differed among three open habitats: burned stands, recent clearcuts, and open wetlands, and whether it differed in relation to the size of clearcut patches. We also examined how detectability of each species varied with time of day, season and weather conditions. Site occupancy for the Eastern Whip-poor-will and Common Nighthawk averaged 0.413 and 0.437, respectively. We found no significant difference in occupancy of either species in relation to burned stands, recent clearcuts, or open wetlands, although Eastern Whip-poor-will occupancy tended to be higher in burned stands. Occupancy did not show a linear relationship with patch size but neither species was found in the smallest open patches (<3 ha), perhaps indicating a minimum size threshold, although further study is needed. The detection of each species was positively correlated with the occurrence of the other species, suggesting that they were both selecting similar site characteristics. Detectability for Eastern Whip-poor-will was highest after sunset and increased over the course of the breeding season, while for Common Nighthawk, detectability was similar during and after sunset and decreased over the season. Our results suggest that Eastern Whip-poor-will and Common Nighthawk show similar preference for natural and managed open sites and that recent clearcuts may provide early successional habitat in the absence of burned stands. Our results also extend the known breeding range of Eastern Whip-poor-will, which further emphasizes the need for future research on these poorly studied species in the boreal forest. [ABSTRACT FROM AUTHOR]

Highlights: [•] I studied behaviour of nightjars foraging under risk of predation by red foxes. [•] Microhabitat choice and body positioning behaviour are based on vegetation structure. [•] Nightjars select for particular cover features as a means to facilitate aerial escape. [•] Prey may not avoid predators, but may manage their escape options from encounters. [ABSTRACT FROM AUTHOR]

Abstract: Many birds living in regions with seasonal fluctuations in ambient temperatures (T a) typically respond to cold by increasing insulation and adjusting metabolic rate. Seasonal variation in thermal physiology has not been studied for the Caprimulgiformes, an order of birds that generally have basal metabolic rates (BMR) lower than predicted for their body mass. We measured the metabolic rate and thermal conductance of Australian owlet-nightjars (Aegotheles cristatus) during summer and winter using open-flow respirometry. Within the thermoneutral zone (TNZ; 31.3 to 34.8 °C), there was no seasonal difference in BMR or thermal conductance (C), but body temperature was higher in summer- (38.2±0.3 °C) than winter-acclimatized (37.1±0.5 °C) birds. Below the TNZ, resting metabolic rate (RMR) increased linearly with decreasing T a, and RMR and C were higher for summer- than winter-acclimatized birds. The mean mass-specific BMR of owlet-nightjars (1.27 mL O2 g−1 h−1) was close to the allometrically predicted value for a 45 g Caprimulgiformes, but well below that predicted for birds overall. These results suggest that owlet-nightjars increase plumage insulation to cope with low winter T a, which is reflected in the seasonal difference in RMR and C below the TNZ, rather than adjusting BMR. [Copyright &y& Elsevier]

Bouts of torpor are characterized by substantial reductions in body temperature and metabolic rate. Many birds in the order Caprimulgiformes use torpor; however, there is conflicting evidence whether or not Common Nighthawks (Chordeiles minor) have this ability. The purpose of our study was to examine whether free-ranging nighthawks enter torpor. Three out of eight birds that were monitored entered torpor on a total of four occasions. Our results suggest that torpor is not used as commonly as it is in other species of Caprimulgids providing incentive for further research to explain the ecological determinants of torpor use in Caprimulgids. [Copyright &y& Elsevier]

In 2017, Gang Liu and colleagues published a paper in this journal in which they described the first mitochondrial genome of Japanese Sparrowhawk Accipiter gularis (Aves, Accipitriformes). The paper included two phylogenies (one based on full mitogenomes, the other on mitochondrial 12S/16S rRNA sequences) that placed this species among the goshawks and sparrowhawks (genus Accipiter). These phylogenies also included a previously published mitogenome of Grey Nightjar Caprimulgus indicus. Here, we show that the published mitogenome of A. gularis is a chimera of three species (a sparrowhawk, a buzzard and a dove), and that the published mitogenome of C. indicus is a chimera of two owl species. Phylogenetic re-analysis showed substantial differences from those published by Liu et al. (2017): the A. gularis sequence was placed among Streptopelia doves in the 12S/16S rRNA tree, and the C. indicus sequence was placed among Otus owls in the mitogenomic and mitochondrial 12S/16S rRNA trees. The phylogenies in Liu et al. (2017) showed several other peculiarities: (i) the inclusion of Javan Hawk-eagle Nisaetus bartelsi in the mitogenome tree (whereas no mitogenome is available of this species and no such sequence has been described in the literature), (ii) reciprocal monophyly of the genera Buteo, Leucopternis and Buteogallus (whereas multiple previous studies have shown these to be para- or polyphyletic), and (iii) the placement of Black-chested Buzzard Eagle Geranoaetus melanoleucus and Crane Hawk ' Geranoaetus ' (= Geranospiza) caerulescens as sister species (whereas all previous studies have shown these to be distantly related). Close examination of the figures in Liu et al. (2017) revealed that both phylogenies have been manually prepared or modified. The evidence indicates that Liu et al. (2017) published phylogenies that were not based on existing data but were fabricated to reflect preconceived ideas about phylogenetic relationships. The phylogenies published by Liu et al. (2017) give the impression that the mitogenomic sequence described in their paper (A. gularis) and another one (C. indicus) described by Zhao et al. (2016) are authentic and correctly identified, whereas in reality these sequences are highly problematic chimeras. The term 'scientific data laundering' is proposed for the practice of hiding poor or erroneous research data with fabricated or falsified figures. • This manuscript presents evidence that a complete mitochondrial genome of a sparrowhawk published by Gang Liu and colleagues in a paper in Biochemical Systematics and Ecology in 2017 is not an authentic sequence of this species but represents a chimera of three different species (a sparrowhawk, a buzzard and a dove). • The manuscript also presents evidence that the authors of the aforementioned paper have fabricated false phylogenies to cover-up this problematic genome, and that of a nightjar previously published by another team, which is also a chimera (of two owls). To our knowledge this is the first known case of scientific fraud in phylogenetics. [ABSTRACT FROM AUTHOR]