ABSTRACT Deer production options were modelled in two contrasting environments, Otago and Hawkes Bay, New Zealand, to estimate greenhouse gas emissions, productivity and profitability. A standard New Zealand deer farm was compared to the deer production scenarios: (1) increasing hind longevity through improved reproductive performance, (2) improving animal health management to increase weaner growth, (3) pre-winter finishing using larger hinds and superior growth genetics sires or (4) shifting to a mixed velvet antler/venison enterprise. Production (kg product/ha) increased as scenarios 1–3 were applied, being greatest for scenario 3, in both environments (+21% and +2% in the Otago and Hawkes Bay environments respectively). Production increases in the Hawkes Bay environment were muted by the inclusion of beef and sheep enterprises. Production in Otago and Hawkes Bay was reduced in scenario 4 by 12 and 7% but achieved increased gross margin (33% and 20% respectively). Some small differences in the magnitude of response were seen between the environments. Changes in total GHG emissions per hectare ranged between +4.6% and −6.7%. GHG emission per $ gross margin was reduced by up to 15%–21%. Altering production options in the deer industry altered total GHG emissions per hectare and reduced GHG emissions per kg of product.