The NZ dairy herd increased 82% between 1990 and 2019, with some of the largest increases in Canterbury and Southland. Neal Wallace investigates the future of dairying in those regions and talks to some innovators who are confident that with the use of technology and management changes, dairying has a future.
A five-year project to help Canterbury dairy farmers reduce their environmental footprint is paying early dividends, with 70% of those in the Selwyn catchment already meeting initial nitrogen loss targets of 30%.
DairyNZ solutions and development lead advisor Virginia Serra says preliminary results reveal that after three years of its Meeting a Sustainable Future project, most Selwyn farmers are ahead of Environment Canterbury’s (ECan) preliminary emission reduction targets.
“Another 20% are well on track to achieving it and are receiving support to get there,” Serra said.
Nationwide regulations introduced last July capped synthetic nitrogen fertiliser applications at 190kg N/ha/year.
ECan targets for dairy farmers in the Selwyn catchment require that by 2022 farmers must lower nitrogen losses by 30% compared to a baseline figure averaged over the 2009-2013 period.
In Hinds, nitrogen losses must be 15% lower by 2025, 25% by 2030 and 36% by 2035.
A recent survey of 234 of the 450 farmers in the Selwyn and Hinds catchments revealed all were reporting positive environmental changes from shrinking their environmental footprint.
The survey revealed 81% have improved irrigation systems or effluent management, some have altered stocking rates or are using plantain to capture nitrogen.
Dairying has grown rapidly in Canterbury, with the number of dairy farms almost doubling from 632 to 1149 in the 10 years to 2015.
The average herd size is 912 compared to the national average of 413.
Last November ECan extended its Land and Water Regional Plan throughout the province, setting new quality limits for ground and surface water, meaning lower nitrogen-loss limits, higher minimum flows, a cap on water extraction and the exclusion of livestock from a broader range of waterways.
“The plan change introduces requirements for some farms in these areas to further reduce their nitrogen losses and to exclude stock from more water bodies,” Councillor John Sunckell said in a statement at the time.
The synthetic nitrogen fertiliser cap applies to all grazed land, except for grazing of livestock on arable crops.
Farm managers are required to record nitrogen purchases, use and type and application rates, including the percentage of nitrogen component by dry weight in other fertiliser mixes and the rate at which it was applied.
All dairy farm managers must supply an annual report on their use to their regional council starting from July 31 next year.
Selwyn catchment data sourced from dairy and irrigation companies alongside a DairyNZ survey shows farmers were using Farm Environment Plans (FEPs) to reduce their footprint and improve water quality by managing nitrogen, phosphorus, sediment and E.coli.
Trials are being held with 40 farmers on how to adjust, and that knowledge is shared with local farmers.
“Achieving these results is not easy and farmers are working hard to deliver,” Serra said.
Further change is coming for Canterbury farmers, with a new integrated plan for Canterbury to be notified by ECan by 2024 under the Essential Freshwater package.
It will introduce new rules and regulations for freshwater, coastal areas and Regional Policy Statements.
How that will impact dairy farming, ECan says it is too early to judge.
In the 2019-20 summer, ECan sampled 55 freshwater and 46 coastal sites, of which 76% of freshwater sites and 91% of coastal sites are considered as being generally suitable for contact recreation.
All lake sites were graded as fair or better compared to 64% of river sites.
Primary contact recreation was suitable in every coastal beach and all but one harbour.
A third of all estuary sites are unsuitable for bathing.
Four freshwater and two coastal bathing sites improved a grade, while four sites (three freshwater and one coastal) decreased a grade.
Half of monitored shellfish gathering sites are considered suitable for collecting and consuming shellfish safely.
Read more articles in the special report series “Dairying has a future“