A Lizard in my Lettuces

Today there was a lizard in my lettuces. A copper skink (Oligosoma aenea) to be exact. I was out picking some leaves to from our Green Oak Leaf and and Pink Freckles lettuces and it quickly scuttled away. It was a beautiful rich bronze-brown, and about 10 cm long (or 4 inches for my USA readers).

Copper skink. This isn't the one from my garden (that one wouldn't wait for a photograph) but another one  seen recently in Auckland. 


As an ecologist, this is something to be celebrated. Copper skinks aren't like slugs or snails - introduced pests that voraciously prey on my vegetables - but are a lizard species unique to New Zealand that FEED on my garden pests. I feel honoured that this "production-focused" area of my garden has been deemed an appropriate residence by local wildlife. Copper skinks are only found in New Zealand, and whilst still the most commonly occurring native lizard in my city, are increasingly under threat from land "development" - that euphemism for "bulldoze the trees and build something", and are preyed upon by many of the mammalian predators we introduced to this land (including stoats, ferrets, weasels, ship rat, Norway rat, house mice, hedgehogs, and the list goes on). We really did stuff it up when we set about enriching this land with species from our respective homelands! But what copper skink really like is not so much pristine native forests but lots of cover and hiding places, some sunshine to bask in, and plenty of small invertebrates to eat. So my garden with compost heaps (three of them!), and ramshackle wooden garden edging, dense plantings of vegetables to smother the weeds, and lots of thick mulch, is quite a happy environment for my local reptiles. In fact, in my professional work, its sometimes surprising where this species turns up. I have searched through mature forest within proposed subdivisions and roads, only to find them in wood piles or under discarded rotting carpet and corrugated iron or in piles of broken concrete. Which tells me that "biological treasure" can be found in strange places, even a lettuce patch.

So how can we be better stewards of our world in our vegetable gardens? How do we encourage courgettes and copper skinks? (hey, I am a sucker for alliteration). As I have previously alluded to, encouraging helpful wildlife and increasing the food production within your patch is, for the most part, complimentary. Here are a few starters:


  • Mulch heavily to retain moisture and reduce weed growth. As the mulch rots, it will also add humus to the soil, further increasing moisture retention and soil nutrients. Mulching is great for skinks, as they love to hide under it to avoid predators such as rats. 
  • Raise your garden beds using wooden surrounds (I use railway sleepers and whatever other scraps of timber I can find). Raised beds improve soil drainage and increase soil temperature over the wet winter months, and provide additional hiding places for small creatures. My railway sleepers have holes in them where they formerly had bolts going through them. 
  • Minimise the use of pesticides. I occasionally resort to some pesticide use for problematic infestations of aphids, but I only do so if plants are getting very stressed by them. Don't leap for a chemical fix until other options (including "do nothing") have been exhausted. If an insect isn't causing harm, its probably performing some useful purpose in nutrient or soil cycling, or is prey for something else that is of benefit.
  • Compost. While emptying a compost bin I once found a copper skink happily living inside the compost bin! I guess it gained plenty of warmth from the decomposition process, and didn't have to go far to get its dinner. 
  • And for something more controversial, don't get a cat, or if you do have one, don't replace it when it dies of old age. Cats are notorious predators of our reptiles, many of which are threatened species. Did you know there are about 100 species of lizards in New Zealand, which gives us more species by land area than Australia (which is regarded as the global hot spot for reptile diversity). Living in the city doesn't excuse cat ownership -  the ornate skink, which has an conservation status of "At Risk-Declining", is found throughout Auckland City.
All of which is quite a digression from my usual gardening prose, but then I did promise to write about anything that makes me tick. 

Till next time,

Tim