Unusual association between Ornithonyssus bursa (Berlese 1888) (Mesostigmata: Macronyssidae) and Parabuteo unicinctus (Temminck, 1824) (Accipitriformes: Accipitridae) in Paraíba State, Brazil

Ornithonyssus bursa (Berlese, 1888), known as the tropical fowl mite, is a hematophagous mite of domestic and wild birds. This mite can bite humans accidentally, causing “gamasoidosis,” “avian-mite dermatitis,” or “bird-mite dermatitis” in tropical and subtropical regions of the world. In Brazil, O. bursa was previously recorded parasitizing birds of the orders Charadriiformes Huxley, 1867, Columbiformes Latham, 1790, Galliformes Temminck, 1820, Passeriformes Linnaeus, 1758, Strigiformes Wagler, 1830, and Tinamiformes Huxley, 1872. Here, we provide a new association of O. bursa with Harris’s hawk, Parabuteo unicinctus (Temminck, 1824) (Accipitriformes: Accipitridae) and the first record of this mite species in the Paraíba State, Brazil.

Optimization of avian perching manoeuvres

Perching at speed is amongst the most challenging flight behaviours that birds perform1,2, and beyond the capability of current autonomous vehicles. Smaller birds may touchdown by hovering3-8, but larger birds typically swoop upward to perch1,2 – presumably because the adverse scaling of their power margin prohibits slow flapping flight9, and because swooping transfers excess kinetic to potential energy1,2,10. Perching is risky in larger birds6,11, demanding precise control of velocity and pose12-15, but it is unknown how they optimize this challenging manoeuvre. More generally, whereas cruising flight behaviours such as migration and commuting are adapted to minimize cost-of-transport or time-of-flight16, the optimization of unsteady flight manoeuvres remains largely unexplored7,17. Here we show that swooping minimizes neither the time nor energy required to perch safely in Harris’ hawks Parabuteo unicinctus, but instead minimizes the distance flown under hazardous post-stall conditions. By combining motion capture data from 1,563 flights with flight dynamics modelling, we found that the birds’ choice of where to transition from powered dive to unpowered climb minimizes the distance from the landing perch over which very high lift coefficients are required. Time and energy are therefore invested to maintain the control authority needed to execute a safe landing, rather than being minimized continuously as in technical applications of autonomous perching under nonlinear feedback control13 and deep reinforcement learning18,19. Naïve birds learn this behaviour on-the-fly, so our findings suggest an alternative reward function for reinforcement learning of autonomous perching in air vehicles.

The Harris Hawk (Parabuteo unicinctus) in Urban Areas of Argentina: Arrival in Mar Del Plata City and Green Area Use in Buenos Aires City

Urbanization has a negative impact on raptor species diversity and abundance. However, some species can adapt to urban areas, and the process of city colonization by raptors has been documented scarcely in the Northern Hemisphere. Information about city colonization by raptors in the Southern Hemisphere is null, and studies about habitat use by raptors are scarce. The objectives of this study were: (1) to describe an event of Harris Hawk (Parabuteo unicinctus) arrival in Mar del Plata city, Argentina, and (2) to analyze its green area use in a recently colonized city, Buenos Aires. Long-term data collected during 2002–2019, along an urbanization gradient of Mar del Plata, was used to describe the city arrival by the Harris Hawk. Surveys of green areas in Buenos Aires were used to model the Harris Hawk occurrence in relation to green area size and isolation to other green spaces. The Harris Hawk arrival was observed during 2019, mainly in periurban areas of Mar del Plata, and at least three pairs were breeding. In Buenos Aires, the occurrence of the Harris Hawk in green areas was related to the proximity to other large green areas. The results obtained suggest the importance of green areas for raptor colonization in cities.

GAVILÁN DE HARRIS Parabuteo unicinctus DEPREDANDO UNA SERPIENTE

En Taura, provincia de Guayas, Ecuador, observé y fotografié el 17 de julio de 2019, a las 08h30, un individuo adulto de Parabuteo unicinctus depredando una serpiente. El reptil medía c. 70 cm de longitud y c. 2 cm de diámetro, era de color verde con el vientre más claro; probablemente se trataba de un adulto de Leptophis ahaetulla (Colubridae).

The identity of Azara’s description No. 18 “Gavilán mixto pintado” is a juvenile Harris’s hawk (Parabuteo unicinctus)

The classic ornithological work by Félix de Azara “Apuntamientos para la historia natural de los páxaros del Paraguay y Rio de la Plata” was one of the first descriptive texts dealing with the avifauna of the Southern Cone of South America. Azara’s No. 18 “Gavilán mixto pintado” has long been misidentified as a juvenile great black hawk (Buteogallus urubitinga ((Gmelin, 1788)). However, there are clear inconsistencies in the description of the plumage coloration, shape and measurements which make that identification erroneous, and Azara’s No. 18 can in fact be convincingly identified as the juvenile plumage of the Harris’s hawk (Parabuteo unicinctus (Temminck, 1824)). The description by Azara contains numerous diagnostic characteristics for that species, and the measurements provided by him are inconsistent with those of the great black hawk, yet remarkably similar to those provided by the same author for the description of the adult No. 19 “Gavilán mixto obscuro y canela”. No scientific names have apparently ever been based on Azara No. 18.

A near-infrared spectroscopy (NIRS) device unveils oxygenation levels in skeletal muscle and brain of a conscious Harris’s Hawk (Parabuteo unicinctus)

We measured the regional saturation of oxygen of hemoglobin (rSO2) and the total hemoglobin index (HbI) in the brain and skeletal muscles of a conscious Harris’s Hawk by a near-infrared spectroscopy device (NIRS). The oxygenation levels of the breast were significantly lower than the cerebral parts. A flight exercise significantly increased the rSO2 and HbI of the breast. The breast surface temperature significantly increased in response to flight training by a thermography. NIRS enabled us to measure changes in the oxygenation levels of brain and skeletal muscles in a conscious Harris’s Hawk before and after a moving task.

Riqueza y abundancia de rapaces diurnas del Cañón de Fernández, Lerdo, Durango

El monitoreo biológico es esencial para comprender la dinámica poblacional, los procesos ecológicos y los problemas emergentes. En este estudio determinamos la riqueza y abundancia de las rapaces diurnas en el Parque Estatal Cañón de Fernández en Durango, México. Detectamos 11 especies, cinco de éstas están bajo alguna categoría de riesgo según la Norma Oficial Mexicana 059-2010: gavilán pecho canela (Accipiter striatus), gavilán de cooper (A. cooperii), aguililla negra menor (Buteogallus anthracinus), aguililla rojinegra (Parabuteo unicinctus) y aguililla pecho rojo (Buteo lineatus). Las especies más abundantes fueron Coragyps atratus, Cathartes aura y Buteo jamaicensis. El hábitat donde obtuvimos más registros fue el bosque de galería. Las rapaces del área ven amenazada su conservación por la pérdida de hábitat, cacería y electrocución.

Bloqueio do plexo braquial em Gavião-asa-de-telha (Parabuteo unicinctus) com auxílio do estimulador de nervos periféricos:

Traumas na medicina veterinária aviária são ocorrências comuns que frequentemente necessitam de intervenção cirúrgica. Associado à anestesia geral, a técnica de bloqueio do plexo braquial pode ser empregada no reparo de fraturas e danos teciduais. Objetivou-se avaliar a eficácia do bloqueio do plexo braquial no trans e pós-operatório em cirurgia de osteossíntese em úmero, realizada em um Gavião-asa-de-telha (Parabuteo unicinctus)após trauma. Foi recebido no Centro Médico Veterinário do Centro Universitário São Judas – Campus Unimonte, o animal encaminhado do CEPTAS (Centro de Pesquisa e Triagem de Animais Selvagens) para realização de osteossíntese em úmero diagnosticada por exame radiográfico. O bloqueio do plexo braquial foi a técnica de anestesia locorregional de escolha, realizada pelo acesso subescapular com bupivacaína a 0,375%, guiada pelo estimulador de nervos periféricos, instrumento auxiliar considerado o “padrão-ouro” para a localização de nervos e plexos nervosos. A destreza do anestesista e conhecimento anatômico da região associado a técnicas de anestesia locorregional, como a neuroestimulação com o estimulador de nervos periféricos, diminui riscos relacionados à técnica e promove aumento das chances de sucesso de bloqueio.