Alkali bees’ ‘phenomenal’ 50 years
A brightly striped bee hovers over a patch of dirt, and then beelines for a hole in the ground.
It dives into its tunnel, up to half a metre deep, to deliver a load of yellow, freshly collected pollen.
These bees are unlike others in New Zealand. They are the American alkali bee Nomia melanderi, introduced to Marlborough in the 1970s.
Plant and Food Research honorary associate Dr Barry Donovan said alkali bees nesting in Blenheim had done the extraordinary, by surviving 50 years, the latter part without assistance.
Hailing from the salty, desert planes in western United States, they were introduced to New Zealand in 1971 as an ‘‘excellent pollinator’’ of lucerne seed crops.
The Department of Scientific and Industrial Research (DSIR) established the bee in Spring Creek, north of Blenheim, in man-made nest sites.
Donovan said despite several attempts to establish the alkali bees in other countries, these bees were the only known alkali bees outside their home range in the US.
He said the bees had faced significant challenges over the years, and it was ‘‘fortunate’’ that they were still living in wild nests in Marlborough.
In the 1970s, lucerne seed production was a big industry in Marlborough.
‘‘We set to introduce the alkali bee to pollinate the crops,’’ he said.
They went through the development phase through the 70s and 80s of building populations.
‘‘We had over 30,000 alkali bees at one point.’’
But in 1992 DSIR was disestablished and Donovan was made redundant along with his colleagues.
‘‘The alkali bees were just
abandoned. The whole project fell apart,’’ he said.
Growers were left with wild bee populations on their properties, without assistance from researchers or scientists, he said.
Lucerne became a less popular crop in Marlborough, as ‘‘grapes started their relentless march’’.
The alkali bee had also survived the repeated spraying at Dillons Point to eliminate the Salt Marsh Mosquito.
But a few years ago, Donovan found there were small numbers of bees still present in a stop bank on a private property at the end of Dillons Point Rd.
‘‘I kept tabs, every few years . . . there were always a few nests on the stop bank here and then to my horror we learned that the council was going to rebuild the stopbank.
‘‘Fortunately the engineer agreed to take steps to protect the bee nests, but in any case I moved some bee grubs to a new area.’’
He said it was a ‘‘phenomenal story’’ of survival.
‘‘This is the 50th year that they have been consecutively nesting from the original site in Spring Creek.
‘‘To date, the bees appear to be thriving.’’
Alkali bees were the same size as honey bees but could be distinguished by their four yellow, green, red transverse bands on the abdomens of females, and five on males.