10 research outputs found
Making space for disorder in the garden: developing biophilia to conciliate aesthetics and biodiversity
International audienc
Contrasting morphological evidence for the presence of taste buds in Dromaius novaehollandiae and Struthio camelus (Palaeognathae, Aves)
This study, facilitated by the use of immunohistochemistry, indicated the presence of
taste buds in Dromaius novaehollandiae but not in Struthio camelus. Seen at the
light microscope level, the taste buds consisted of follicular cells and receptor cells.
The follicular cells were located at the periphery of the taste bud, essentially
encapsulating the receptor cells. Two morphologically distinct receptor cells were
identified. Immunohistochemical labelling for neurofilament identified gustatory
nerves within the taste bud. The distribution of taste buds in D. novaehollandiae
matched strategic locations in the oropharynx along which food could be sampled,
according to the feeding method described for these birds. Future feeding studies
would be necessary in D. novaehollandiae to determine the importance of taste
discrimination in their diet. This study represents the first confirmed report of a sense
of taste in any ratite species.University of Pretoriahttp://link.springer.com/journal/4352016-09-30hb201
Fish and squid in the diet of king penguin chicks, Aptenodytes patagonicus, during winter at sub-antarctic Crozet Islands
The diet of king penguins, Aptenodytes patagonicus, rearing chicks was studied during three consecutive austral winters (1990, 1991 and 1992) at Crozet Islands. The mean stomach content mass of the 47 samples was 503 g. Percentages of wet and reconstituted masses showed that both fishes (66 and 36%, respectively) and squid (34 and 64%) are important components of the winter diet. Juveniles of the demersal onychoteuthid squid Moroteuthis ingens form the bulk of the cephalopod diet, and this was the main prey by reconstituted mass (57%). Myctophid fish (lantern-fishes) accounted for most of the fish diet, constituting together 32% by mass. The three main species of myctophids eaten in summer by king penguins were either very rare in winter (Electrona carlsbergi) or accounted for a smaller proportion of the diet (Krefftichthys anderssoni = 1.5% by mass and Protomyctophum tenisoni = 4.6%). Five other myctophids, which are rarely consumed in summer, contributed 24% of the diet by mass in winter (Gymnoscopelus piabilis = 18.1%, Lampichthys procerus = 2.4%, G. nicholsi = 1.3%, and Metelectrona ventralis and Electrona subaspera = 1.0%). The greater diversity of prey in winter suggests a more opportunistic feeding behaviour at a time probably marked by a change in prey availability. Both the known ecology of the fish and squid prey and the barely digested state of some items suggest that in winter breeding adults forage in the outer shelf, upper slope and oceanic areas in the close vicinity of the Crozet Islands to feed their chicks. Finally, using king penguins as biological samplers, the present work provides novel data on the previously unstudied mesopelagic/epibenthic marine community in waters surrounding the Crozet Islands. Seventeen myctophid fish have been identified to species level. These include several poorly known species in the southern Indian Ocean. The occurrence of small, nearly intact, cephalopods in the diet of king penguins suggests that spawning grounds of four squid species may be located near the Crozet Archipelago
Patterns and Trends in Urban Biodiversity and Landscape Design
Urbanization destroys or modifi es native habitats and creates new ones with its infrastructure. Because of these changes, urban landscapes favor non-native and native species that are generalists. Nevertheless, cities reveal a great variety of habitats and species, and, especially in temperate cities, the diversity of vascular plants and birds can be higher than in the surrounding landscapes. The actual occurrence of a species, however, depends on habitat availability and quality, the spatial arrangements of habitats, species pools, a species’ adaptability and natural history, and site history. In addition, cities are particularly human-made ecological systems. Top- down and bottom-up activities of planners, land managers, and citizens create the urban biodiversity in general and in detail. Plants and animals in cities are the everyday life contact with nature of the most humans on our earth. The intrinsic interplay of social and ecological systems with a city often forms unique biotic assemblages inherent to that city. To support native biodiversity, landscape architects, conservation biologists, and other groups are linking landscape design with ecosystem structure and function to create and restore habitats and reintroduce native species in cities