The main objective for this study was to establish whether subantarctic expeditions pose a risk for the introduction of alien species. Our main focus was the examination of the logistic operations and people travelling with the Australian Antarctic Program
Report on survey of cargo for V3 - Macquarie Is and Casey November 2000 Dr Dana Bergstrom, The University of Queensland ... Introduction
This report describes preliminary findings of a survey of cargo destined for Macquarie Is on V3. The purpose of the survey was to assess whether the cargo carried organisms that potentially could be introduced to the Macquarie Is ecosystems during ANARE activities.
Fifty six cargo items and 160 gas bottles were observed during the survey. Cargo was examined at the AAD Kingston Store and Macquarie No 4 Wharf just prior to V3 leaving for Macquarie Is and Casey. Only external features of cargo were searched. All cargo items destined for field huts and all gas bottles were examined, the remaining items were chosen randomly, much dependant of what was accessible in the store and shed. In addition the stacking of cargo determined whether or not all sides of cargo could be examined. Bases of cargo were not viewed.
The quantity of alien material found was significant; as a result on sub- samples of material were collected. Preliminary identification of material is reported here. This survey aimed to collect macro elements and not examine the microbial potential of the material.
In addition plants with the vicinity of the Kingston Store were collected as identified. The potential capability of these species on subantarctic islands was assessed.
Summary of findings
Of the 56 cargo items only 13 items appeared to be clean of debris. Of the gas cylinders 36 (22%) of the 120 examined had spider webs present on their top rims.
Considerable amounts of plants debris was found on the cargo, in particular large numbers of Eucalypt leaves and large quantities of Acacia fragments, flowers and other plant parts. Most Eucalyptus leaves had evidence of insect infestation. The potential of these insects to invade subantarctic ecosystems is considered low due to high host specificity (Dr Gimmie Walter UQ, pers com 10/11/00). As yet I have not determined whether the Acacia flowers contained insects or other invertebrates such as mites.
In the contaminant material, of significant threat to subantarctic ecosystems were the following: propagules (seeds and fruits) of six taxa including grass, daisy (Asteraceae) and Caryophyllaceae, live insects and invertebrates (collembolla, flies, mites, insect pupa, caterpillar, snails and spiders). In addition dead insects were also found including a bee and weevil. These insects are from groups not found at present of Macquarie Is.
It was obvious that significant plant material had blown in through the store doors from the local vicinity. Of the 21 species of plant collected from outside the Kingston Store I believe that 16 are of high to very high risk potential to subantarctic ecosystems.
Not examined in this survey was the potential of microbial contaminants but it can be reasoned that this too would be considerable high as soil and other debris was found. Further assessment of this threat is needed, particularly as such a threat spans both subantarctic and Antarctic ecosystems.