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California’s Butterflies |
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Butterfly Gardening |
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Southern California is rapidly being developed and much of the natural environment is already gone. Most of the landscape has been replaced by houses and commercial buildings. Unfortunately as we develop these lands we alter the native habitat. We not only put up houses which eliminates habitat, but we also replace the native plants with ones from Africa, Australia, New Zealand, the Far East, etc. Most of the plants used in landscaping are not native plants. These non-native plants can be sterile or have little to no nutrition for our native wildlife. In fact, part of the reason we grow these plants is because they are resistant to damage by native insects.
From a garden nursery’s viewpoint, the less damage observed on a plant the more valuable it will be to a customer. For this reason many plants sold by nurseries have gone through selection for reduced plant damage due to insect feeding. This selection pressure on our native plants reduces their environmental value. It would be best if society could change its sense of values, which will in turn affect the thinking patterns of nurseries. If we only buy plants that are fed upon by our native insects then nurseries will find ways to accommodate us as purchasers.
Many birds and lizards depend on herbivorous insects as a food source. Most herbivorous insects, which include almost all butterfly species, will feed exclusively on native plants, but not on non-native plants. As an example, larvae of the common Monarch butterfly feed only on species of Milkweed (Asclepias). Without milkweeds there will be no monarch larvae in the area to produce new monarch adults. If an area loses native milkweeds, the only monarchs observed in the area would be ones migrating through on their way to a different destination.
Butterflies need several things for survival:
1) a specific plant or plants which larvae feed upon, 2) places to hide and roost, 3) nectar sources, 4) places to mud-puddle, 5) places to diapause, and 6) for some lycaenid butterflies, the right species of ant.
Males of some butterfly species need to feed or drink at mud puddles. These extra sources of water can be valuable for both sexes during dry years. For some butterflies diapause sites are also needed, particularly for those species that remain in diapause for many years. The right species of ant can be very important in the presence of specific butterflies. These ants protect the larvae from predators and parasites. For instance, Plebejulina (Plebejus) emigdionis requires a specific species of ant in addition to a specific plant in order to survive.
A well manicured yard does not provide good areas for butterfly larvae and adult butterflies to hide. Good habitat for butterflies is not appreciated by the various Home Owner Associations, which require plants to be trimmed and lawns to be mowed. We need to change our ways of thinking about what we see as beautiful. Grass lawns require incredible amounts of water and can contribute to environmental waste. We should think that a beautiful yard is one that supports the greatest diversity of animals and plants and not one that has all of its plants neatly trimmed.
By providing habitat for butterflies one helps prevent butterfly species from being extirpated from areas and eventually from going extinct. Areas that are good for butterflies are also good for other insects. Southern California is rich in insect diversity compared to other areas in North America. This is due, in part, to our rich native flora.
In order to create a good butterfly habitat in your yard you first need to determine what butterflies could occur there. Start by opening up a local book on butterflies and figure out which butterflies are most likely to occur in your area. Looking at range maps can further delineate which species are likely to be present. California butterflies occur over a wide variety of elevations, but many are specific to particular areas. Go through the list and determine which species can occur on your property based on elevation and whether you are on the desert or coastal side of the mountains. Going out for a walk and observing the butterflies that occur in the area will also help, but it will only give you a slim percentage of the total butterfly species that live in your area. |