Population size. This is one of the fundamental attributes used to assess the status of a flyway population. The sizes of waterbird populations are constantly changing, yet population size estimates are usually only measured periodically (updates once in every 3-12 years). Therefore, it is important to use metrics that provide the best characterisation of the population size until the next assessment. If the population is fluctuating, the best characterisation of the ‘current’ population size is to present the five-year mean of the population estimate +/- the 95% confidence intervals (if a sufficient number of annual surveys have taken place). In the case of populations that are clearly increasing or decreasing, the five-year mean would be a biased characterisation of the ‘current’ population size, therefore the five-year maximum or minimum is used, respectively. When the population estimate is not based on yearly counts, but only minimum and maximum estimates are available, the geometric mean of these two values is used because it provides a more robust estimate of the population size than the arithmetic mean.
Population size. In 1985, it was estimated that Rwanda was home to more than 1 000 Grey Crowned Cranes. The population is currently estimated to be between 300 and 500 individuals, distributed between the main wetland systems in the country. Rugezi Xxxxx is the primary site for Grey Crowned Cranes in the country, but they are also found in Akagera National Park, Kamiranzovu Wetland inside Nyungwe National Park, Nyabarongo Wetland and Akanyura Wetland. The latter two, although Important Bird Areas, have no protected area status or protection. Grey Crowned Cranes are declining in Rwanda largely due to their removal from the wild for the domestic pet trade and habitat loss primarily to agriculture. The “Peat to Power” plans for Rwanda, whereby peatlands will be removed for power generation will no doubt escalate this decline further.
Population size. With a population estimate of a few 1 000 in the 1985 population estimate for Tanzania, the country currently has less than 2 000 individuals and no real evidence to suggest that there are more than a 1 000. They are widespread across the country, with two non-breeding concentrations on the North West slopes of Mount Kilimanjaro and in the caldera of Ngorogoro Crater. Breeding has been recorded from the northern parts of the country (including Serengeti National Park, Tarangire National Park, Arusha National Park, Lake Manyara National Park and Katavi National Park) and in Usangu, which has been incorporated into Ruaha National Park.
Population size. The South African population of Grey Crowned Cranes is the only increasing population across their range. They have increased from a few 1 000 birds in 1985 to an estimated 6 500 in 2012. The population is found along the eastern highland grasslands of the country, with the primary population found on private land in the southern Drakensberg region, traversing the northern parts of the Eastern Cape Province and the southern reaches of the KwaZulu-Natal Province. The species is increasing in the country, with an estimated 44% increase between 2001 and 2012. However, threats to the species include habitat loss, the illegal removal of birds for the captive trade market, collisions on overhead wires, electrocutions on electrical infrastructure and poisoning.
Population size. In 1985, the population in Zambia was estimated at less than 1 000 individuals. Recent estimates put the population at more than 2 000 individuals. Key sites for cranes in Zambia include Liuwa Plains National Park and the entire Barotse Floodplain in western Zambia, Lochinvar and Blue Lagoon National Parks on the Kafue Flats, Kafue National Park, South Luangwa National Park and Tondwa Pans. The Zambian population, although potentially in decline in some areas, is likely stable to increasing country wide. This is largely due to the fact that the key areas for Grey Crowned Cranes in the country are National Parks and are afforded some degree of protection. That said, the encroachment of the alien invasive Mimosa pigra on the Kafue Flats, uncontrolled fires and human disturbance all pose a serious threat to the species.
Population size. Large AS PROVIDED BY THIS CONTRACT, XXXXXXX SPECIALLY UNDERSTANDS AND AGREES TO ASSIGN ITS RIGHT TO RECEIVE ANY AND ALL REIMBURSEMENT PAYMENTS UNDER THIS CONTRCT TO THE CERTIFIED VENDOR. OAG Contract No. 1336718 OAG CERTIFICATIONS AND ASSURANCES
Population size. The resident population of St.Helens is 177,600 people (2015 mid- year estimate, ONS). This has increased over the last 7 years and is predicted to increase year on year over the next 25 years. The current General Practice (GP) registered population of NHS St Helens CCG (Clinical Commissioning Group) is 195,523 (HSCIC, April 2016); this indicates that a number of residents from outside the Borough are registered with St.Helens GPs. According to 2012 data from NHS England, 96% of St.Helens residents are also registered patients with NHS St Helens CCG practices.
Population size. The global populations of procellariiform seabirds vary in size greatly, from a few tens (e.g. some gadfly petrels Pterodroma spp.) to millions (e.g. several shearwaters Puffinus spp.). IUCN categories of threat are largely based on population trends, but given the huge ranges in population sizes that occur within the order, it is considered that rarity should also be a factor influencing the choice of candidate species for ACAP listing. ACAP is an international agreement. Thus it seems reasonable that species should breed within at least two states to be considered strong candidates. In other words, single-country endemic procellariiforms Xxxxxx & Xxxxx: Agreement on the Conservation of Albatrosses and Petrels 3 might be accorded a lower priority for ACAP listing becasue conservation efforts directed at them will be largely of a domestic and not of an international nature. However, although several single-country endemic species are already listed within ACAP, all face threats within international waters because of their migratory nature (next subsection). Closely allied to the above criterion, the highly pelagic nature (in the great main) of the procellariiform species means that they often undertake long migrations at sea. This suggests that most species will travel within the territorial and Exclusive Economic Zone (EEZ) waters of more than one individual state and also within international waters. A high level of migratory behaviour might then suggest that inclusion within ACAP is warranted, because any conservation actions required will not be the sole responsibility of any one state. Many procellariiform species face land-based threats at their breeding grounds from such factors as alien species, pollution, disturbance and habitat loss. Such threats have been recognized by ACAP. It seems reasonable to consider that if similar land-based threats are faced by a species in more than one breeding-range state, then its listing within ACAP might lead to an improvement in its conservation status, by, for example, transfer of expertise (“capacity building”) and by collaborative activities. Lastly, the main driving force behind the negotiation and adoption of ACAP was the ongoing threat facing procellariiform seabirds within international waters from fishery interactions, especially with longlining gear (Anonymous 2000, Xxxxxx et al. 2006). It was realized that such threats could be addressed only through the combined actions of many states—breeding-range an...
Population size. Prior to the 1960’s Grey Crowned Cranes were wide spread and commonly seen across Burundi, with less than 600 reported in the range wide population estimate in 1985. They are now rarely seen, and only in small family groups across the country. Burundi currently has less than 100 Grey Crowned Cranes left, with recent sightings of family groups at the northern tip of Lake Tanganyika, on the Burundian Plateau in Gitega Province, the lacustrine area in the Kirundo Province and in the Malagarazi River Basin in Rutana Province.
Population size. The South African population of Grey Crowned Cranes is the only increasing population across their range. They have increased from a few 1 000 birds in 1985 to an estimated 6 500 in 2012. The population is found along the eastern highland grasslands of the country, with the primary population found on private land in the southern Drakensberg region, traversing the northern parts of the Eastern Cape Province and the southern reaches of the KwaZulu-Natal Province.
