The need to support local wildlife was promoted in the book "Bringing Nature Home" by Professor Doug Tallamy of the University of Delaware (website here). Tallamy says in one survey of butterflies and their food plants, 350 caterpillars were found on local native plants for every 10 found on exotic plants. He also pointed out that 90% of insect herbirvores (caterpillars and leaf-eating beetles) are specialist eaters, feeding on only a few species that they are adapted to. Adult butterflies will test the leaf of a plant before laying eggs, by tasting it with their feet.
Mike talked about creating a wildlife cafe in your backyard, providing food, water - such as in a 'puddling place' - and shelter, and listed the extraordinary number of different insect groups that might live in a suburban backyard:
- butterflies
- moths
- shield bugs
- weevils
- cicadas
- stick insects
- jewel bugs
- plant hoppers
- assassin bugs
- lady beetles
- two-tailed leaf beetles
- bees (2000 species of solitary bees in Australia; about 12 species of stingless bees.
One native bee species that is often in local backyards is the blue-banded bee. The females hatch out of the mud and meet up with males who have been 'roosting' on twigs or tendrils around the garden. Other solitary bees may lay eggs in a bee hotel made of bamboo or a bundle of sticks of both soft and hard wood (even dead Lantana), but the bundle must be at least 150mm deep, as female and male eggs are laid at different ends of the stick. The hole size should be no bigger than 10 mm.
Some of the animals that may be attracted to our gardens could help control pests. For example, the Ladybeetle and its larve eat aphids. The Blue-eyed Lacewing nymph (antlion) eats psyllids, insects that commonly attack lillypillies. The crab spider eats Crusader bugs on Citrus trees.
Some examples of local plants that provide resources for insects are:
- Brisbane Wattle (Acacia fimbriata) - supports Imperial Hairstreak butterfly and Wattle Notodontid moth.
- Wombat Berry (Eustrephus latifolius) - feeds the Two-tailed Leaf Beetle
- Dogwood (Jacksonia scoparia) - supports caterpillars of three butterfly species
- Love Herb (Pseuderanthemum variabile) - supports five butterfly species.
A longer list of local plants that you could put in your garden is at https://pollinatorlink.files.wordpress.com/2012/09/pollinator-link-plants-seq-ver-1-0.pdf Some of these are available to N4C members at our nursery - members can take home 10 free plants per year for their gardens.
Mike shared the link to his Pollinator Link website where you can sign up your garden as a Pollinator Link garden. If 10% of backyards signed up, there would be water, food and shelter available every 150 to 300m, throughout Brisbane. Even apartment balconies can be Pollinator Link gardens. At Mike's website you can also download the pdf instructions for bee hotels, habitat tripods, garden designs and plant lists. A BCC grant enabled him to pay artist Paula Peeters for the designs and copyrights so they are now able to be distributed free of charge.
