ML320318411
Colaborador
Data
Localização
- Idade
- Não especificado
- Sexo
- Não especificado
Detalhes da observação
First observation at 0734. 4 counted on property. First-ever sighting of this species here since surveys began in spring 2017! Two male/female pairs seen associated with ponds in reach 4 and reach 3. I was surprised to see them on the reach 4 ponds since these ponds are very recent (created this winter), completely lack surrounding vegetation or emergents, and presumably are not very rich in invertebrates. Nevertheless, we saw Buffleheads swimming on at least two of these ponds. They also landed on some of the more eastern ponds in reach 3. No diving (i.e. feeding) behavior observed; however, the Buffleheads were relatively skittish when we watched them, so it is unsurprising that they were not foraging while we were watching. According to Birds of the World, aquatic insects are primary freshwater prey of Buffleheads, particularly odonate nymphs, Corixidae bugs, and chironomid larvae. Preliminary entomology work in 2020 documented a diverse assemblage of odonates and at least 2 species of Corixidae on the reach 3 ponds; I have not studied Diptera here yet, but presumably chironomids are common here as well. At this point, it is biologically impossible that there are odonate nymphs in the reach 4 ponds (unless lotic species, eg. Ophiogomphus severus, have managed to survive the change in habitat). It will be interesting to survey the reach 4 ponds for other insect taxa this spring and to observe their colonization by odonates, emergent plants, and other life. On the return, we still saw 2 pairs on the ponds in spite of the large volunteer crew (ca 25) installing wattles in reach 4. At this point the Buffleheads were using ponds as far as possible from the volunteers and were quite flighty. Detections (number 15-minute intervals in which the species was detected): 4 on property.
Informação técnica
- Modelo
- COOLPIX P900
- ISO
- 800
- Distancia focal
- 357 mm
- Flash
- Flash did not fire
- f-stop
- f/6.5
- Velocidade do obturador
- 0.01 sec
- Dimensões
- 4608 pixels x 3456 pixels
- Tamanho do ficheiro original
- 6.19 MB