If a pair of monarchs came into a New Zealand garden on 1 September and the female started laying eggs, consider this.........…
Scientific data tells us that each female monarch can lay 300 - 500, or even over a thousand, eggs. Let’s say she lays 500, of which half are females. So on or about 1 October these 250 females start laying and lay 250 x 250 = 62,500 eggs.
This continues all season. It’s a perfect season for monarchs. None of them are going to get diseases, eaten or parasitised.
1 December there are 15,625,000 eggs
1 January 3,906,250,000 eggs
1 February 97,656,300,000,000,000 eggs
1 March 24,414,100,000,000,000,000 eggs
That’s quite a few monarch butterflies flying around!
In the REAL world some monarch caterpillars are destined to feed other species – even the soil. We’re fortunate that monarchs slot into our New Zealand native ecosystem and don’t have any negative effect on our native plants or animal life.
If there were a lot of wasps (as in previous years) the monarchs wouldn’t “control” the swan plant and it could get listed as a pest plant, with the seed blowing into gardens, farmland and our NZ native forest.
REF: Moths and Butterflies of NZ Trust
January 10 at 8:29pm · Auckland ·