General Impact
Axis axis often congregate in large groups and return to, and remain in, areas for long periods of time. When they occupy riparian areas, they heavily trample and browse vegetation. During the rut (reproductive season) significant impact to trees occurs when bucks rub and polish their antlers on bark, frequently leading to the death of the trees. This results in a loss of the stability that vegetation provides, with resulting destabilisation of stream banks, changes in stream flow and increased erosion and sedimentation of streams, ponds and rivers. When deer populations become too large, their trailing behaviour creates dirt pathways through even the thickest of vegetation. These trails can lead to significant erosion and, in wet forest areas, increase runoff by decreasing the mossy layer available that would normally retain water (Anderson, 1999; and the National Park Service, 2004).
Anderson (1999) reports that A. axis cause crop damage when natural forage is scarce. In their introduced range, they can also compete directly with cattle for forage. Although they prefer to graze grass, it is clear that the deer will respond to available forage conditions and eat what is available to them, which causes damage to local native species. A. axis can also graze forage grasses and other plants much closer to the ground than domesticated species. In extreme drought conditions, A. axis will eat bark off trees (Anderson, 1999).
A. axis have been found to carry and transmit bovine tuberculosis and several other diseases. They carry common parasites that can directly affect humans if and when droppings enter freshwater systems. Parasitic zoonoses harbored by A. axis include: leptospirosis, cryptosporidiosis, and strains of Escherichia coli (Anderson, 1999).
Location Specific Impacts:Point Reyes National Seashore (United States (USA)) 
Agricultural: Fallow deer and Axis axis deer affect the park's ranches by damaging fences through depredation of pasture and supplemental livestock feed; by overgrazing fallow fields, and through a possible increase in the risks of disease transmission (National Park Service, 2004).
Competition: Some of the more serious effects Axis axis have at the protected area include possible competition with, and displacement of, native tule elk (Cervus elaphus nannodes) and black-tailed deer (Odocoileus hemionus) (particularly in high deer density or low forage conditions) (National Park Service, 2004).
Economic/Livelihoods: The cost to the park for staff, equipment, vehicles and supplies to monitor and manage non-native deer currently totals approximately $140,000, or 2.5% of the park annual budget. The diversion of resources to the management of an exotic species is at the expense of preservation and the re-establishment of native species and habitat at the protected area (National Park Service, 2004).
Habitat alteration: Heavy use of the riparian habitat by Axis axis impacts on native wildlife who are dependent on this habitat (National Park Service, 2004).
Pathogenic: There is the potential for Axis axis transmitting disease to native ungulates (National Park Service, 2004). Maui Is. (United States (USA))
Competition: On Maui, Axis axis are now frequently encountered in the cane fields owned by HC & S Sugar. Deer have been seen co-existing with cattle in other areas of the island. The cattle are in poor condition (nutritionally) and the deer have continued to thrive, even under extreme drought conditions (Anderson, 1999). Hawaii (United States (USA))
Herbivory: Axis axis adaptability and high variability in forage consumed, is a serious problem in Hawaii. Art Medeiros has documented a 'foraging hierarchy' near Puu o' Kali under extreme drought conditions, whereby A. axis will eat the most palatable item available until it is scarce. They will then choose the next most palatable item and eat that. In the peak of the drought of 1999, the Axis axis were eating highly unpalatable bark off trees (Anderson, 1999).
Human nuisance: The trailing behavior of Axis axis has caused damage to a variety of culturally or archaeologically significant sites. Significant damage to native sites, heiaus and old Hawaiian stone walls where deer consistently pass through in large numbers have been documented (Anderson, 1999).
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