Browsing in Victorian forests - results of the 1998 statewide survey.  I. D. Sebire.  June 2001.  29pp. (unpubl.)

SUMMARY

In 1998, a statewide survey was undertaken to determine the extent of problems caused by browsing to regenerating areas in native State forests in Victoria. This survey covered regeneration operations during the years 1994 to 1996 and followed on from a survey conducted in 1995 and covering regeneration in the years 1992 to 1994 (Wallace and Fagg, 1999). The survey confirmed previous findings that browsing of eucalypt regeneration is a serious problem in a number of localities, and that current control methods are costly and often ineffective.

The main findings were:

• Statewide incidence. Severe browsing affected 3% (49/1409) of coupes at the first attempt at regeneration, and 7% (93/1409) were moderately browsed. The proportions rose to 25% (41/165) severe and 15% (24/165) moderate browsing for second-attempt regeneration and reforestation coupes.
• Forest types affected. High elevation mixed species (HEMS) was the forest type most affected in regeneration at first attempt; 7% of coupes were severely affected and 19% of coupes were moderately affected. The proportions rose to 33% severe and 23% moderate in second-attempt regeneration and reforestation coupes. The low elevation mixed species (LEMS) forest type was less affected at first attempt at regeneration, 5% severe, 1% moderate, but the incidence was higher in reforestation and second-attempt regeneration coupes, 30% severe and 7% moderate. In mountain ash forest type browsing was insignificant in first attempt coupes but significant (19% severe, 13% moderate) in second-attempt or reforestation coupes. Browsing was present in alpine ash, box-ironbark and red gum forest types, but confined to small areas and more prevalent in reforestation or second-attempt coupes.
• Localities affected. Browsing was a serious and persistent problem at Mt. Cole, Cobaw Ranges, Mt. Disappointment, Bendoc, Buldah, Stanley Plateau, Black Range, Bendigo, Pyrenees and Gellibrand.
• Browsing species. The native swamp wallaby (Wallabia bicolor) was again clearly the major browsing species, being identified in 86% (122/142) of all coupes where moderate or severe browsing was reported at first attempt at regeneration, and in 95% (61/64) at second attempt. Swamp wallaby was reported in all forest types, from box-ironbark to alpine ash. Rabbits were reported as a significant source of browsing damage. Other browsing species such as deer and eastern grey kangaroo were of relatively minor importance.
• Year of regeneration/reforestation. For first-attempt regeneration coupes there was little difference between regeneration years other than a slightly lower amount of browsing damage in 1995 than in 1994 and 1996. HEMS forests, however, did suffer from a higher level of browsing damage in 1994 with 34% moderate or severe, compared to 1995 - 18%. For second-attempt or reforestation coupes, 1995 was the year with most browsing damage.
• Control methods. Most methods of browsing control have been ineffective when browsing pressure has been high. Fencing was effective when combined with a shooting program but otherwise is not effective. Shooting alone was not effective. The wallaby repellent WR1 was relatively effective in providing browsing protection when browsing pressure was light but otherwise was ineffective.
• Comparison with previous survey. For first-attempt regeneration coupes there was little difference in the amount of browsing damage between the 1995 and the 1998 survey. In second-attempt or reforestation coupes there was a significant increase, from 11% to 25%, in the amount of severe browsing. This increase was noted in all forest types except alpine ash.

It was concluded that if certain areas cannot be satisfactorily regenerated at reasonable cost because of browsing, the re-scheduling of harvest of 'at risk' areas, until affordable control techniques are identified, may need to be considered.