With Monarchs and Milkweeds - Part one was posted on February 6. If you have not already read this please scroll down.
Lesson No. 3: There is an organism named Ophryocystis elektroscirrha, which for obvious reasons is more commonly known as OE. The images above show one of my caterpillars and later its chrysalis infected by this parasite. For comparison to the right is an image of a healthy chrysalis. From my research I learned that emergent infected adult butterflies die off during their migration flight and thus do not carry and spread the spores of this disease to other butterflies in the over wintering colony. Thereby keeping this disease of our native monarchs in check. Secondly when you have a year round food source for monarchs you also have a year round site for OE which is transferred from butterfly wings when the butterfly is nectaring or laying eggs. OE spores are then consumed by the butterfly's larvae. OE is naturally kept in balance when native milkweeds die back. Not so with the perennially growing non-native milkweeds in warmer climates.
As I monitored my monarchs I noticed a majority weren't making it. Some not developing normally never emerged, others struggled to emerge, fell to the ground and died. These likely were stricken with OE. Another natural predator on many lepidoptera species is the tachinid fly. This fly oviposits its eggs into caterpillars where they consume their host then emerge and drop down on long silky threads to pupate in the ground. As shown below I observed these as well taking a toll on my monarch family.
Lesson No. 4: In reading some of the literature on this topic I learned that there is a bit of controversy regarding the benefits vs. the dangers of growing tropical milkweed. Because of severe habitat loss - not to mention use of herbicides in agriculture fields - monarch butterfly advocates believe that tropical milkweed plants in home gardens provide food and nectar which helps the monarch survive. Scientists however are more cautionary and advocate the use of local native milkweed species. Well, this makes perfect sense to me. But where can you find these native milkweeds which scientists are recommending we use? Certainly not in our big box store garden centers.
So I went searching online for native milkweeds at my favorite SoCal native plant nurseries. And I was a little disappointed. Las Pilitas Nursery in Escondido: '0'; Tree of Life Nursery in San Juan Capistrano: '0' - Well, actually they did not answer their phone and they do not have an online availability list; Rancho Santa Ana Botanic Garden in Claremont: '0'; Theodore Payne Foundation in Sun Valley ...'0'.
Monarch butterflies are so threatened, and yet very popular; so why are their host plants not more readily available? I kept up my search though and at last discovered a source, Moosa Creek Nursery in Valley Center. According to their inventory list they had Asclepias fascicularis and Asclepias speciosa, both terrific milkweed species. Searching further I found that Matillija Nursery way up north in Moorpark also had these same species in their inventory. I wonder if there were a higher demand for our native milkweeds would they be more easy to come by.
Lesson No. 5: If you want to do the right thing sometimes you can not take the easy path and to get native milkweed, this year anyway, I may have to take the long path down to Valley Center. But isn't it worth it? Actually what would really be best for monarch fans and the butterflies alike would be to have Home Depot adopt the little darlings as their mascot and promote the conservation of the monarchs through the sale and planting of native milkweed species. Home Depot corporate colors are orange and black, so what a great fit and what a PR coup!
Until then.......if you want to grow your own native milkweed plants you can find seed sources for several of these native species here at this excellent monarch website: Monarch Butterfly Garden
Here also are two excellent seed sources for California native seeds who also carry several milkweed species: Larner Seeds and Sierra Seed Supply.
Here are links to photos and information on some of our native milkweed species.
Narrowleaf or whorled milkweed
and possibly my favorite, and along with narrowleaf milkweed, the easiest to grow:
The Xerces Society is also the go to place for information on all things butterflies, check out their milkweed guide here.
Well now back now to my butterflies. Despite disease and parasites I did have three chrysalises which produced what appeared to be healthy normal butterflies. Here are some of my photos from this exciting event. All photos taken using my Nikon 100mm F2.8 macro.
So now I have a better sense of why folks get so attached and dedicated to these delightful creatures and I am especially grateful for this journey I have been allowed to take. Just wonderful this is and what wonders there can be in your own back yard.
3/3/2016 07:36:49 pm
I'm happy to report that just this week the news reported that the Monarchs in Mexico are thriving this year. There's a bumper crop, or whatever the terminology is for a booming population.
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Michael Wall - Hemet, CA