The genome sequence of the European nightjar, Caprimulgus europaeus (Linnaeus, 1758)

We present a genome assembly from an individual female Caprimulgus europaeus (the European nightjar; Chordata; Aves; Caprimulgiformes; Caprimulgidae). The genome sequence is 1,178 megabases in span. The majority of the assembly (99.33%) is scaffolded into 37 chromosomal pseudomolecules, including the W and Z sex chromosomes.

Flight altitude dynamics of migrating European nightjars across regions and seasons

Avian migrants may fly at a range of altitudes, but usually concentrate near strata where a combination of flight conditions is favourable. The aerial environment can have a large impact on the performance of the migrant and is usually highly dynamic, making it beneficial for a bird to regularly check the flight conditions at alternative altitudes. We recorded the migrations between northern Europe and sub-Saharan Africa of European nightjars Caprimulgus europaeus to explore their altitudinal space use during spring and autumn flights and to test whether their climbs and descents were performed according to predictions from flight mechanical theory. Spring migration across all regions was associated with more exploratory vertical flights involving major climbs, a higher degree of vertical displacement within flights, and less time spent in level flight, although flight altitude per se was only higher during the Sahara crossing. The nightjars commonly operated at ascent rates below the theoretical maximum, and periods of descent were commonly undertaken by active flight, and rarely by gliding flight, which has been assumed to be a cheaper locomotion mode during descents. The surprisingly frequent flight-altitude shifts further suggest that nightjars can perform vertical displacements at a relatively low cost, which is expected if the birds can allocate potential energy gained during climbs to thrust forward movement during descents. The results should inspire future studies on the potential costs associated with frequent altitude changes and their trade-offs against anticipated flight condition improvements for aerial migrants.

Habitat Selection by the European Nightjar Caprimulgus europaeus in North-Eastern Poland: Implications for Forest Management

Research Highlights: Intensive forest management practices generally have a negative effect on biodiversity. However, the creation of new, open habitats as a consequence of timber harvesting within large areas of woodland may be favorable to some bird species. Background and Objectives: Habitat selection of the European Nightjar Caprimulgus europaeus in a coniferous woodland area in northeastern Poland was studied in order to specify management recommendations. Materials and Methods: To define the influence of various environmental parameters on territory occupation, 11 micro- and 3 macrohabitat factors were analyzed. Results: Denser vegetation in the ground layer deterred birds from nesting in clearings with such characteristics. Moreover, Nightjars preferentially inhabited sites adjacent to young stands of trees. Birds preferred plots with a higher number of clearings in the neighborhood, as this enabled them to enlarge their foraging area. Other microhabitat factors (e.g., the type, age and area of clearings), as well as macroscale factors like distances to the forest edge, nearest roads and human settlements, were of no importance. Conclusions: Knowledge of the Nightjar preferences may be useful in working out a compromise between an appropriate level of clear-felling and conservation of other bird species requiring preservation of old tree stands.

Gli uccelli del Parco Regionale della Maremma e aree limitrofe (Grosseto, Toscana, Italia)

Il Parco Regionale della Maremma è una area protetta di 8902 ha nel settore costiero centrale della provincia di Grosseto, Toscana meridionale. Gli habitat che rappresentano l’area protetta possono essere così brevemente descritti: foce del fiume Ombrone e zone umide della Palude della Trappola; Monti dell’Uccellina (cima più elevata: Poggio Lecci, 417 m s.l.m.); un ampio comprensorio interno e pianeggiante dove coesistono attività zootecniche e coltivazioni agricole. Lo sviluppo costiero raggiunge i 25 km circa. Sono presenti 6 Siti della Rete Natura 2000 classificati come ZSC − Zona Speciale di Conservazione − secondo la Direttiva “Habitat” 92/43/ CE e/o come ZPS − Zona di Protezione Speciale − secondo la Direttiva “Uccelli” 2009/147/CE. La maggior parte dell’area presenta una scarsa rete viaria e limitati insediamenti umani con copertura boschiva in larga parte dovuta a formazioni vegetali sclerofilliche mediterranee. In questo lavoro viene presentato un elenco commentato degli uccelli noti per l’area protetta a partire dalla sua istituzione avvenuta il 05/06/1975 sino al 31/12/2018. In totale, le specie di Uccelli rilevate sono 295 (62,1% delle specie della Toscana ed il 52,5% delle specie note in Italia), mentre le specie nidificanti certe o probabili in tempi recenti (2008-2018) sono 84. Le specie di interesse comunitario presenti nell’Allegato I della Direttiva “Uccelli” 2009/147/CE sono 88, mentre quelle classificate come SPEC 1-3 “Species of European Conservation Concern” sono 33. L’area, con le zone umide “Bocca d’Ombrone” e “La Trappola” comprese nella Macrozona “Maremma Grossetana”, ricade all’interno della qualifica di sito di importanza internazionale per lo svernamento di Anser anser e Mareca penelope; inoltre è sito di importanza nazionale per Mareca strepera, Anas crecca, Anas acuta, Spatula clypeata, Ardea alba, Platalea leucorodia, Phoenicopterus roseus, Recurvirostra avosetta, Pluvialis apricaria, Calidris alpina, Vanellus vanellus, Gallinago gallinago, Numenius arquata, Tringa erythropus e Tringa totanus. L’area protetta è di importanza per specie nidificanti in Direttiva 2009/147/CE legate agli specchi lacustri costieri e agli spazi marini, ad incolti, pascoli, così come a zone con vegetazione arborea e arbustiva sparsa su affioramenti rocciosi, margini di boschi, ambienti parzialmente allagati ed ai litorali sabbiosi, quali ad esempio, con dati minimi, Pandion haliaetus (1 coppia), Burhinus oedicnemus (7-8 coppie), Charadrius alexandrinus (1 coppia), Caprimulgus europaeus (25 coppie), Coracias garrulus (13-15 coppie), Lanius collurio (1-5 coppie), Lullula arborea (10 coppie) e Anthus campestris (6-7 coppie). Dal 2015 si segnala il consolidamento della nidificazione di Ardea cinerea, rilevandone per la prima volta la riproduzione come garzaia.