It's early spring, and a patch of endangered shrubs in the Blue Mountains of New South Wales has started to bloom.
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patch → start → Wales
Crouching among the plants is a group of scientists on a delicate mission.
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group → crouch → mission
Armed with tweezers, the scientists "emasculate" tiny pink and white flowers by removing the male reproductive organ called an anther.
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scientists → arm → organ
They're after specks of pollen to hand-pollinate plants that are struggling to reproduce.
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that → pollinate → plants
Essentially, they're collecting sperm in the hope of performing the plant equivalent of artificial insemination.
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they → collect → insemination
Zieria covenyi blooms from September to December.
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covenyi → bloom → December
It has only two known populations in the world, both in the Blue Mountains National Park.
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It → have → Park
Zieria covenyi flowers have both male and female parts: the orange-coloured male anther holds pollen, and the female stigma at the centre receives pollen carried from other flowers by pollinators.
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stigma → have → pollinators
If all goes to plan, the shrubs will produce fruit and seed that eventually becomes a plant with its own unique genetics.
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that → go → genetics
While some plants at the national park's Breakfast Creek have fertile pollen, scientists suspect another population some 6 kilometres away at Narrow Neck Peninsula may be sterile.
uncertain
population → have → Peninsula
"What I usually say is, these plants are shooting blanks," Angelina Ellis, an honours student at the University of New South Wales (UNSW), says.
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Ellis → say → Wales
"That's why we're looking for sperm donors.
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we → look → donors
"
The goal of UNSW's Threatened Rare Endemic Plant Research Group is to uncover the extent of the plant's fertility issues in both locations.
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goal → uncover → locations
"How sterile is sterile?" Chantelle Doyle, UNSW conservation botanist and Ms Ellis's supervisor, says.
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says → say → ?
"If we find plants with viable pollen, can we cross-pollinate and create seed with plants that are sterile?"
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that → find → plants
The collected pollen is stored in a cool bag, and the scientists trek over to Narrow Neck.
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scientists → collect → Neck
The difference between the two locations is stark: while the Breakfast Creek shrubs stand up to 2 metres tall, they only reach knee height at Narrow Neck.
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they → stand → Neck
The team works fast to "inseminate" flowers on some plants, leaving others untouched as a control group.
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team → work → group
Then the flowers are encased in "wedding party favour" bags, as Dr Doyle calls them, to protect against pollinators.
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Doyle → encase → pollinators
It will take two months to see if the pollination attempt has worked.
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attempt → take → months
Most Zieria covenyi are thought to reproduce asexually from shoots growing from the roots of the parent plant in a cloning process called "root suckering".
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covenyi → think → process
Genetically speaking, they are the same organism.
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they → speak → ?
Even with a conservation plan, the shrub will remain at heightened risk if it cannot diversify its population.
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it → remain → population
"[Cloning] is a really good adaptation to persisting in an area when the habitat and the climate are optimal," Dr Doyle says.
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Doyle → persist → area
"But when it shifts, [the shrubs] don't have any genetic diversity to adapt."
Genetic rescue programs, like the work the scientists are undertaking in the Blue Mountains, aim to increase genetic variation within a population of flora or fauna to make it more resilient to pests, diseases and environmental changes.
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it → shift → pests
One of the first examples of genetic rescue in Australia was a program to translocate mountain pygmy possums in the Victorian Alps.
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One → translocate → Alps
Two months after hand pollinating the Zieria covenyi shrubs, Ms Ellis and Dr Doyle return to Narrow Neck Peninsula to check the fruits of their labour.
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Ellis → pollinate → labour
One by one they sift through the organza "party favour" bags, keeping an eye out for small black seeds that Dr Doyle says look like "fly poo".
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Doyle → sift → poo
There are a few moments of false hope when they notice black dots in the bags.
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they → be → bags
But then those dots start to crawl.
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dots → start → ?
They are bugs scavenging the dried flowers.
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They → scavenge → flowers
As the hot day wears on, it becomes clear this hand pollination attempt has not been successful.
"
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attempt → wear → ?
The female part of the plant works.
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part → work → plant
They produce a flower that is receptive and attracts pollinators," Dr Doyle says.
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Doyle → produce → pollinators
"But then it just drops off and never produces a fruit.
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it → drop → fruit
The seed never develops because it doesn't get fertilised."
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it → develop → ?
Although the team pollinated flowers within hours, the donor pollen might have degraded in transit.
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pollen → pollinate → transit
"And just because the other population produces [seed] doesn't necessarily mean that it has 100 per cent pollen viability," Ms Ellis says.
"
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Ellis → produce → viability
It's actually relatively low from what I can see.
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I → see → what
There are a handful of flowers still intact that might produce seed.
uncertain
that → be → seed
…and 12 more, not listed.
The Aporia