Earlier monitored releases

My own involvement in western ringtail possum releases started in March 2005 and quickly turned into the hardest part of the rehabilitation work as finding adequate release sites was even then close to impossible.

The known requirements made for a long list but were often contradictory, e.g.  animals had the best release age,  but inclement weather disallowed releases. However, the most common problem was the lack of a release site that promised successful establishment of a colony.
Manpower was also a major problem!

It turned out that the most important requirement when selecting a release site was knowledgeable, willing people at the site.
Support was needed for all areas – predation issues (monitoring, baiting, trapping), release monitoring and emergency intervention (storms etc.).  

Example 1:  
Release on a 50 acres mixed bush lot with lots of ‘food species’ but not ‘Busselton quality’, large peppermint dominated area along a creek line, moderate brushtail presence, fox baited (also on neighbouring properties) , people patrolled, possum boxes and waterers supplied.

Monitoring in areas with dense bush was very limited as it was too time- and labour intensive.
A camera was rotated around the spots where animals were released but footage was only used to check for presence of any animals.

As this release was quickly deemed successful, more animals were added in quick succession and I can only estimate the number of releases –
approximately  40.
Sightings on camera were very frequent, occasional spotlighting surveys always found a number of animals, however dead animals were also found which in my view indicated overstocking.

People on neighbouring properties reported ringtail sightings as a novelty which would hint at dispersals establishing outside the release property.

Release activity was ceased for a number of years – only taken up again in 2017 - but ringtail sightings have been ongoing for at least 8 years and breeding activity has been observed.

Example 2: 
Release on a small special rural lot (about 5 acres) with extensive planting work aiming at providing wildlife habitat, but still in the development stage, very low to zero brushtail presence, no baiting allowed, constant trapping, ongoing patrolling efforts and monitoring of releases and predators by cameras, provision of boxes and stationary cages, if needed supplement feeding provided, constant access to water (waterers)

The careful release of only 5 animals has been followed by spotlighting also in nearby areas, scat searches, drey searches, frequent checks of possum boxes and camera monitoring.

Now in the eighth year, a half an hour check reveals  approximately 4 animals, there is clear breeding activity including twins and offspring are surviving. The little colony is persisting, increasing and dispersing into surrounding areas.

The main problems for such a small area is the risk that predation can quickly render the population unviable, a risk of overstocking and of reduced genetic variety.  

Planting activity in the surrounding areas with an attempt to influence neighbours to create habitat and allow corridors between patches, aims at limiting those risk factors. Further careful adding to the gene pool might be beneficial.