Aircraft events correspond with vocal behavior in a passerine

Airports can affect birds by hindering acoustic communication. Here, we investigated the impacts of aircraft events on vocal behavior in wood thrush (Hylocichla mustelina) breeding one mile from an airport in Ithaca, NY, USA. We identified the number of wood thrush songs between 0500 and 0800 h at various distances from the airport and on days with various morning flight schedules. We also analyzed the number of sites from which birds sang during the peak of aircraft events (proxy of number of wood thrush). We found that birds sang more from 0600 to 0640 h when there were aircraft events during this period. This increased vocal behavior is likely explained by increased song output per individual wood thrush, rather than more wood thrush vocalizing. Increased song rate may negatively affect wood thrush fitness through increased energetic demands and/or time tradeoffs with other important behaviors, such as foraging. Identifying the noise thresholds associated with fitness costs (if any) and how different behavioral strategies (i.e. changing the pattern of vocalizations) may allow individuals to evade these costs would be useful for establishing conservation policy in breeding habitats used by passerines, such as the wood thrush.

The changing trend in songbirds’ abundance, variety and physical condition in Connecticut’s forestry habitat

Songbirds are facing rapid population declines in Connecticut due to habitat loss. Man-made habitats such as powerline corridors are one of the few remaining ideal habitats for songbirds in the state. This study aims to determine if the abundance and variety of song-birds in four selected forests (i.e. Naugatuck State Forest, Sharon Audubon Society, Miles Wildlife Sanctuary, and Great Mountain Forest Species Variety) in Connecticut show patterns of decline from 2005 to 2014. This study also compares the physical condition of songbirds captured along a powerline corridor in the Naugatuck State Forest with those captured in the rest three non-fragmented forests in Northwestern Connecticut using Mann-Whitney U tests. Weight and wingspan are used as indicators of bird physical condition. The results demonstrate that the three non-fragmented forests experienced a steady decline in the variety of songbirds between 2005 and 2014. In addition, songbirds’ abundance decreased steadily during the same period, except that of the ovenbird (Seiurus aurocapilla) and wood thrush (Hylocichla mustelina) in Miles Wildlife Sanctuary. The results from the Mann-Whitney U test have shown that after sex- and age-controlled features, the physical conditions of the three selective songbirds – veery (Catharus fuscescens), ovenbird, and wood thrush – tend to be better in the Naugatuck State Forest than in the three non-fragmented forests – Sharon Audubon Society, Miles Wildlife Sanctuary, and Great Mountain Forest Species Variety. Given are recommendations on how to protect the shrubland habitat along powerline corridors and how to create the shrubland habitat in non-fragmented forests.

New feather mites of the genus Amerodectes Valim and Hernandes (Acariformes: Proctophyllodidae) from passerines (Aves: Passeriformes) in Georgia, USA

Eight new species of the feather mite genus Amerodectes Valim and Hernandes, 2010 (Proctophyllodidae: Pterodectinae) are described from passerines (Aves: Passeriformes) in Georgia, USA: Amerodectes cathari sp. n. from Catharus ustulatus (Nuttall) (Turdidae), A. haemorhous sp. n. from Haemorhous mexicanus (Muller, PLS) (Fringillidae), A. helmitheros sp. n. from Helmitheros vermivorum (Gmelin) (Parulidae), A. hribari sp. n. from Geothlypis trichas (Linnaeus) (Parulidae), A. hylocichlae sp. n. from Hylocichla mustelina (Gmelin) (Turdidae), A. passerinae sp. n. from Passerina ciris (Linnaeus) (Cardinalidae), A. seiurus sp. n. from Seiurus aurocapilla (Linnaeus) (Parulidae), and A. spizellae sp. n. from Spizella passerina (Bechstein) (Emberizidae). An updated world checklist of Amerodectes species and a key to species recorded and potentially expected in North America (USA and Canada) are proposed.