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Falklands Conservation |
Since the earliest recorded settlement by French colonists at Port Louis, the natural peat beds of the Falkland Islands have been used as a relatively convenient source of fuel. Peat is traditionally cut to expose a vertical face, one yard in depth. In peat beds of sufficient depth, successive yards of peat may be cut, which therefore exposes deeper and hence older peat layers.
West Point Island lies about 1/4 mile off the north west arm of West Falkland. Sheep farming started on its 3,100 acres (1255ha) in 1879 and peat has been excavated for at least a century. About 3/4 miles west of the settlement lies a previously heavily used peat bog, which is now rarely cut. It is situated on a small plateau in the centre of a valley at an altitude of 220-250ft, between two peaks (Black Hog Hill and Rocky Ridge Hill), each of 500ft. The valley slopes north-east to south-west, from sea level at Cat Cove, to 100ft cliffs at Devils' Nose.
It is in this peat bog that large numbers of bird bones have been found. This is by no means a recent discovery. Such bones were originally noticed whilst excavating the peal for fuel. Their presence was first noted by Hattersley-Smith and Hamilton in 1950 who implied that bones were first noticed there in the early 1930s. Robin Woods examined the deposit in 1962 and observed that bones were distributed in a vertical layer of at least one foot (30cm). According to Hattersley-Smith and Hamilton, three successive layers of peat, each a yard deep, have been removed, which means that the bones originally lay beneath at least nine feet of peat. It is not known how deep the 'layer' of bones, or indeed the peat bed extends. The lateral extent of the bone deposit is also unknown.
During December 1996, we visited the site where we excavated bone material from a small sample area. The bones are situated in very dense peat and are relatively abundant. Having been preserved in moist peat, they are particularly soft and fragile. Once exposed to the sun and air, the bones rapidly dry and become extremely brittle. The density of the peat surrounding the bones also makes their location and removal an awkward procedure.
As Hattersley-Smith and Hamilton found, the bones appear to be exclusively avian. The majority of them are complete, undamaged limb bones, although some more fragile skulls and synsacra (pelvis) were also found, as well as toes and claws of birds of prey. A surprisingly diverse number of species were found, ranging in size from a probable finch (maybe the resident Black-throated Finch Melanodera melanodera) to Striated Cararcara Phalcoboenus australis .
In order to identify the bones they were taken to the Natural History Museum at Tring, England, where more detailed studies can be carried out. However, to prevent the bones from drying and becoming brittle, they must first be cleaned and treated with a dilute PVA glue solution. This delicate and time consuming procedure will ensure that the bones are preserved in a suitable condition for handling. They can then be identified, using the large collection of comparative material housed at the Natural History Museum.
Identifying the bones will show whether they are of species still present in the Falklands, or of species now only recognised on the South American mainland. it is also possible that new species, previously unknown, may be found.
These bones were probably deposited many hundreds of years ago, long before the human occupation of the past 220 years. We therefore intend to request that samples of bone are subjected to a carbon-dating process because they could provide information that far pre-dates any current knowledge of the Falkland Islands avifauna.
The dating, preservation and identification procedures are currently at an early stage. When more information has been gathered, we intend to publish the results and shall also inform members of Falklands Conservation through the pages of 'TheWarrah.'
We are extremely grateful to Roddy Napier for allowing us access to the peat bog and permission to remove a sample of bones. His hospitality during our stay was overwhelming. Staff at the Department of Agriculture in Stanley gave help freely, particularly in obtaining the relevant permits required for shipment of bone material. The staff of the Palaeontology Department of the NHM, particularly Adrian Doyle, are also acknowledged for instruction in preservation techniques.
Reference: Hattersley-Smith, G and Hamilton J E (1950) A Recent Deposit of Bird Bones in the Falkland Islands. Nature, 166
Following the Penguin Census and FIG Coastline Survey during 1995/96, the 1996/97 fieldwork season could have been an anti-climax but it turned out to have many interesting facets of its own.
We began with negotiations to find two new sites. Our monitoring programme had never covered the south-west of the Islands, and did not include a study site on West Falkland, so Port Stephens was chosen to cover this region. In addition, Saunders Island was selected for a monitoring and banding programme on Albatross, but it also turned out to be one of our best sites for monitoring Penguins. At one location here there are six species of Penguin and thousands of Albatross within one kilometre of coast.
The six sites now being monitored are the limit for the current level of resources.
The first counts are of occupied nests during incubation of eggs, and this must be completed as soon as possible after egg-laying in November. These counts allow us to observe changes in population.
The second round counts numbers of chicks reared and this must be completed before chicks fledge and leave the rookery (February for Penguins and April for Albatross). From the data gathered we determine how successful a reproductive season each species has had and build up a picture of the factors which influence breeding success rates.
Fieldwork is concentrated into these two periods as close to the optimum time as possible. Unfortunately, this season a flu epidemic spread through the Falklands just after Christmas, knocking people for six, including my field assistant Carol Aldiss, who was taking time off from her usual work for the British Geological Survey. Her illness created a temporary crisis, but the gap was filled by Jeremy Smith, David Green and Dan Holland, a GAP student loaned to us from the Department of Fisheries. Thanks go to them all for their valuable contributions.
Thanks also go to our trusty band of volunteer counters, who monitor certain colonies each year on our behalf. This enables us to greatly increase the number of colonies being monitored.
Virtually without exception, the Penguin and Albatross rookeries had an excellent season, successfully rearing large numbers of chicks. The Gentoo and Magellanic Penguins often exceeded 100% productivity (ie one chick per nest), and the Rockhoppers and Albatross averaged around 80% and 50% respectively. These differences in productivity do not so much reflect differences in seasonal success, but rather differences in breeding strategy.
But the high points of the season for me were seeing a Chinstrap Penguin on Saunders Island, and a Striated Caracara nest at Port Stephens. Not only was this the first I had been close enough to photograph, but it was also the first confirmed breeding of a Striated Caracara on mainland Falklands.
It's now time to enter all the data into our databases and GIS, and to determine what conclusions can be drawn. Plenty to keep me occupied during the winter months, I'm sure.
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Felton's Flower is a low growing prostrate annual. It is highly attractive, with brilliant magenta flowers which open their widest in bright sunshine. The seeds, which are small, shiny and black, usually germinate in late summer, and the plant overwinters as a small seedling. In spring it grows rapidly and the flowers often appear by October, a time when little else is in bloom. The plant stems may reach up to 35cm or more in length while the basal leaves can be up to 1 cm long. It's nearest relatives occur in South America between 35o and 50o South. (Photo by R Lewis-Smith) |
Felton's Flower (Calandrinia feltonii) is endemic to the Falklands. It had been generally regarded as extinct in the wild for a number of years with the surviving population restricted to a tiny number of private gardens. There has been a great deal of interest in recent plans for a reintroduction of the plant to its natural habitat.
In 1996, Sinead Doherty, then employed as a temporary assistant at the Falkland Islands Department of Agriculture (DoA) successfully completed a seven week plant conservation course at the Royal Botanic Gardens (RBG) at Kew. On her return to the Falklands, Sinead drew up a recovery plan for Feltons Flower Calandrinia feltonii (Doherty , 1996), the primary objective of which is the reintroduction into the wild of a genetically viable population of Felton's Flower to the Falkland Islands. Having developed the project thus far, the DoA handed over responsibility for its continuance to Falklands Conservation in late 1996, although they will continue to provide specialist advice and support when required.
The past summer has seen a number of developments. In particular, it has been a surprise to all concerned just how many private gardens across the Islands support flourishing populations of Feltons Flower. A number of the owners of these gardens are assisting Falklands Conservation by answering a questionnaire regarding details of growing conditions, annual success etc and by providing seed for future work. Mention should also be made of the gardening staff of Government House who, in early summer, planted 60 seeds which successfully germinated providing additional seed for work next season.
But perhaps the most significant development has been the possible 'discovery' of plants in the wild. It was reportedly present in the Roy Cover area during the 1970s but there had been no recent confirmed sightings. It appears though, that lower than normal stocking rates of land in the Roy Cove area on West Falkland during the last twelve months has allowed at least one plant to flourish in areas normally grazed by sheep. The overall number of plant species, particularly flowering plants, in this area was also reported to be noticeably higher than normal this summer.
As far as the Recovery Plan goes, we now have a great deal more information available relating to propagation and cultivation, and we also have a good store of seed in hand. This winter it is hoped that 'genetic fingerprinting' will be conducted by Dr Mike Maunder at the RBG at Kew to determine if seed currently being collected is in fact a pure strain native to the Islands. Providing this is the case, the next stage will be to identify sites in the wild where the species might be successfully reintroduced (and protected). A site in the Hill Cove region has already been offered, and it is hoped that others will follow.
Reference: Doherty S (1996) Recovery Plan for Felton's Flower (Caladrinia feltonii) Report for Department of Agriculture, Stanley, FI.
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Patron: HRH The Duke of York CVO ADC Member of the International Union for Conservation of Nature | BirdLife International Representative |