70 research outputs found
HISTORIC AND RECENT WINTER SANDHILL CRANE DISTRIBUTION IN CALIFORNIA
Understanding the geographic distribution and long-term dynamics of winter foraging areas and night roost sites of sandhill cranes (Grus canadensis) is important to their conservation and management. We studied sandhill crane distribution in Californiaâs Central Valley from December 2012 through February 2013. We mapped observed flock and night roost locations. Flock locations occurred between Tehama County in the north and Kern County in the south. Flocks were concentrated in the northern Sacramento Valley, the Sacramento-San Joaquin Delta, the northern San Joaquin Valley south of Tracy to Mendota (including the lower Stanislaus and Tuolumne River floodplains and the Grasslands Region), and the southern San Joaquin Valley in the vicinity of Pixley in Tulare County. We also reviewed records of historic occurrences of cranes in California to interpret the importance of our flock and night roost locations. Although cranes wintered in the Los Angeles, San Diego, and San Francisco Bay metropolitan areas in the 19th and early 20th centuries, they no longer occur in significant numbers in these areas due to widespread habitat loss. Three additional areas which were used in the mid-20th century have apparently been abandoned or are being used only infrequently: the Red Bluff area (along the Sacramento River between Red Bluff and Anderson, Tehama County), the Goose Lake area (Kern County), and the Carrizo Plain (San Luis Obispo County). The primary cause of site abandonment at these sites is loss of suitable foraging habitat (small grain crops). With the exception of the Southern San Joaquin region, crane winter range has expanded in the Central Valley since the 1960s. Range expansion has principally been due to expansion of public wildlife refuges and private sanctuaries, plus improvements in their management (including reductions in hunting disturbance). To improve habitat conditions for cranes across their Central Valley wintering range, we recommend that management be focused on protection, enhancement, and creation of crane habitat complexes, each of which should contain 1 or more roost sites surrounded by sufficient well-managed foraging habitat. The following conservation strategies (listed in order of priority) should be implemented for each major crane wintering region: 1) protect existing, unprotected roost sites by fee-title acquisition or conservation easements (prioritize among sites according to their importance to greater sandhill cranes; G. c. tabida); 2) protect foraging landscapes around existing roosts, primarily through easements restricting development and crop types that are incompatible to cranes; 3) enhance food availability within those landscapes by improving foraging conditions on conservation lands and providing annual incentives for improvements on private lands; and 4) create additional protected roost sites toward the edge of their existing range where birds can access additional foraging areas
A postmodern approach to ecological sustainability : the re-enchantment of Fiji's forests
"Na cava na i sau ni taro ni kena tamusuki na veikau e Viti?â, a vuqa era taroga. Au nanuma ni bibi cake na taro. Kevaka e cala na veitaro e tarogi sa dredre sara me kunei na kena i sau a veiganiti. E gadrevi li me vakavinakataki na kena vakatulewataki? Se na navunavuci vinaka li? Na bula toro cake vakailavo li? Se na i tovo vakavanua? Au nanuma ni vu ni nodra vakacacana na tamata na veika e tu tikivi keda a Viti me vaka na musu kau e vakatau mai na noda i tovo vakavanua. Ia na mataqali tovo vakavanua cava a tokoni e Viti me baleta na kena i tuvaki ni vanua, se tiki ni tovo cava e cala? E Viti e kunei kina na bula veimaliwai ni veimatatamata, ia sa bula ka donumaka e dua na gauna ni veisau you. Na veisau vovou sa kena i tovo na kila ka, kei na i tovo e bucini cake ena yavu ni vakasama e taucoko. Na veisau vovou sa veisautaka na i rairai ni vanua e Viti ka kidomoka na veika kece e vakamareqeti ki na dua na kena yaga e qiqo. Ia, na tamusuki ni vaikau sa vakayacori makawa e Viti ni bera na gauna ni veisau oqo, e na gauna ni bula va-Koloni, ka sa dodonu me rau beitaki ruarua na i tovo e rua oqo. Na nona dusi e dua me beitaki ena sega ni vukea na leqa, ia na veika e rawa ni vakayacori sa i koya na noda taqomaki keda mai na noda vakalecalecava ni sega ni cala na i tovo ena kena vakacacani na veika e tu tikivi keda. Na vei tovo kece sara e dodonu me ra vakaitavi ena kena kunei na bula toro caki. Na i vakarau ena sega ni vunitaki dua mai na i tavi me qaravi. Na kena rawati na i naki ni nodra karoni me tudei na veika bula e tu tikivi keda sa gadrevi kina na vakatulewa matau ka ni veika e dau yaco e sega ni vaka i vakarau. Sa gadrevi talega kina na i tovo ka sega ni okata na kila ka me gaunisala duadua ni kena veivosakitaki na i tuvaki ni vanua. Na kena vakaduavatataki ni veivakasama kei na rokovi ni veika tawa kilai vakakina na veika e tawa siqemi rawa sa rawa ni kunei ena vuqa na i tovo, ka okati kina na vei tovo makawa vaka-Viti kei na nodra na vavalagi. Kevaka e vakasaqarai dina me tudei tu na vanua era bula voli kina na veika bula tikivi keda, na i tavi e tu sa i koya na kena vakasaqarai se kunei vou tale eso na veivakasama vovou kei na kena vakauqeti na nodra bula vakataki ira ga na veika bula.
"What is the answer to deforestation in Fiji?" many people are asking. To find an answer we first need a question. If the wrong question is asked the possibility of an appropriate answer is out of reach. Is better management needed? Is it better planning?
Perhaps it is a greener economy? Or is it culture? I argue that the causes of human induced environmental degradation in Fiji such as deforestation lie in the character of culture. But what culture or cultures do the landscapes of Fiji support, and what aspect of culture is at fault? Fiji is culturally diverse but currently dominated by modernity.
Modernity is a culture of knowledge, and a culture built upon the foundations of a steady state rationality. Modernity has disenchanted the landscapes of Fiji and squeezed all forms of value into the narrow framework of utility. However, deforestation also happened in Fiji before modernity arrived with the colonial British, and so both pre-modern and modern cultures in Fiji must share the blame. Pointing at someone to blame does not solve our problem, but what it can do is prevent us from pretending that cultures are innocent when it comes to environmental disharmony. All cultures are responsible for enacting a sustainable life. Tradition will not hide anyone from that responsibility. Fulfilling the obligation of ecological sustainability requires a rationality of process because reality is in a constant state of flux. It also requires a culture that does not see knowledge as the only way of engaging in a conversation about or with a landscape. A rationality of process and a respect for the unknown and unknowable can be found in many different cultures, including the non-modern Fijian culture and non-modern cultures in the West. If ecological sustainability is what is sought, the task is a discovery or re-discovery of process thinking and a re-enchantment of Nature
Supramolecular Double Helices from Small C-3-Symmetrical Molecules Aggregated in Water
Supramolecular fibers in water, micrometers long and several nanometers in width, are among the most studied nanostructures for biomedical applications. These supramolecular polymers are formed through a spontaneous self-assembly process of small amphiphilic molecules by specific secondary interactions. Although many compounds do not possess a stereocenter, recent studies suggest the (co)existence of helical structures, albeit in racemic form. Here, we disclose a series of supramolecular (co)polymers based on water-soluble benzene-1,3,5-tricarboxamides (BTAs) that form double helices, fibers that were long thought to be chains of single molecules stacked in one dimension (1D). Detailed cryogenic transmission electron microscopy (cryo-TEM) studies and subsequent three-dimensional-volume reconstructions unveiled helical repeats, ranging from 15 to 30 nm. Most remarkable, the pitch can be tuned through the composition of the copolymers, where two different monomers with the same core but different peripheries are mixed in various ratios. Like in lipid bilayers, the hydrophobic shielding in the aggregates of these disc-shaped molecules is proposed to be best obtained by dimer formation, promoting supramolecular double helices. It is anticipated that many of the supramolecular polymers in water will have a thermodynamic stable structure, such as a double helix, although small structural changes can yield single stacks as well. Hence, it is essential to perform detailed analyses prior to sketching a molecular picture of these 1D fibers
HISTORIC AND RECENT WINTER SANDHILL CRANE DISTRIBUTION IN CALIFORNIA
Understanding the geographic distribution and long-term dynamics of winter foraging areas and night roost sites of sandhill cranes (Grus canadensis) is important to their conservation and management. We studied sandhill crane distribution in Californiaâs Central Valley from December 2012 through February 2013. We mapped observed flock and night roost locations. Flock locations occurred between Tehama County in the north and Kern County in the south. Flocks were concentrated in the northern Sacramento Valley, the Sacramento-San Joaquin Delta, the northern San Joaquin Valley south of Tracy to Mendota (including the lower Stanislaus and Tuolumne River floodplains and the Grasslands Region), and the southern San Joaquin Valley in the vicinity of Pixley in Tulare County. We also reviewed records of historic occurrences of cranes in California to interpret the importance of our flock and night roost locations. Although cranes wintered in the Los Angeles, San Diego, and San Francisco Bay metropolitan areas in the 19th and early 20th centuries, they no longer occur in significant numbers in these areas due to widespread habitat loss. Three additional areas which were used in the mid-20th century have apparently been abandoned or are being used only infrequently: the Red Bluff area (along the Sacramento River between Red Bluff and Anderson, Tehama County), the Goose Lake area (Kern County), and the Carrizo Plain (San Luis Obispo County). The primary cause of site abandonment at these sites is loss of suitable foraging habitat (small grain crops). With the exception of the Southern San Joaquin region, crane winter range has expanded in the Central Valley since the 1960s. Range expansion has principally been due to expansion of public wildlife refuges and private sanctuaries, plus improvements in their management (including reductions in hunting disturbance). To improve habitat conditions for cranes across their Central Valley wintering range, we recommend that management be focused on protection, enhancement, and creation of crane habitat complexes, each of which should contain 1 or more roost sites surrounded by sufficient well-managed foraging habitat. The following conservation strategies (listed in order of priority) should be implemented for each major crane wintering region: 1) protect existing, unprotected roost sites by fee-title acquisition or conservation easements (prioritize among sites according to their importance to greater sandhill cranes; G. c. tabida); 2) protect foraging landscapes around existing roosts, primarily through easements restricting development and crop types that are incompatible to cranes; 3) enhance food availability within those landscapes by improving foraging conditions on conservation lands and providing annual incentives for improvements on private lands; and 4) create additional protected roost sites toward the edge of their existing range where birds can access additional foraging areas
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