The Lifecycle of Butterflies

A comparative look at a few southwest species

It’s early May in Phoenix and we’re starting to see lots of blues, and more and more Monarchs, Queens, Yellows, Whites and Skippers. But in my yard there has been an interesting lag the past couple of years – I’ll observe an early generation of butterflies in March/early April, then for a few weeks hardly any butterflies.

Is this cycle unique to my yard, or perhaps it’s related to the natural lifecycle of our butterflies? An early generation becomes active (or migrate in) in March, mate and lay eggs, then a few weeks later the next generation begin to show up in the yard. Let’s look at the lifecycles of some of our butterflies.

Gulf Fritillary

We had a mild winter this year and I’ve seen Gulf Fritillary caterpillars on the passion vine without stop. They are cold blooded though, so cold temps will slow down their metabolism.

Lifecycle: Egg to Adult in 4 – 5 Weeks
Egg stage – 4 to 8 days
Caterpillar – 2 to 3 weeks
Chrysalis – 5 to 10 days
Butterfly – 2 to 4 weeks


The Monarchs develop from egg to adult in about 4 weeks:

  • Eggs hatch in about 4 days. Females lay one egg on a plant; in their lifetime they will lay 100-300 eggs.
  • Caterpillars go through five instars in about 14 days. When they first hatch, caterpillars eat the egg shell for nourishment. Similarly, they eat shed skin after every molt.
  • Chrysalis stage is about 14 days

The overwintering generation lives about eight months due to a biologic change that stops reproductive behavior during their migration south. The summer generations of the butterfly live only three to five weeks.

Great Purple Hairstreak

Great Purple Hairstreak

Lifecycle: Egg to adult in 5 – 8 weeks

  • Egg – 4 to 6 days
  • Caterpillar – 3 to 4 weeks 
  • Chrysalis – 10 to 20 days
  • Adult – 4 to 10 days

Painted Lady

Lifecycle: Egg to adult in 4 – 8 weeks

  • Egg – 4 to 14 days
  • Caterpillar – 2 to 4 weeks
  • Chrysalis – 7 to 14 days
  • Adult – 6 to 20 days

Milkweed Bugs: Friend or Foe?

What are those reddish-orange and black bugs crawling all over your milkweed, and are they harmful? Like many elements in an ecosystem, the answer fits into the gray zone.

Large Milkweed bugs (Oncopeltus fasciatus) and Small Milkweed bugs (Lygaeus kalmia) love your milkweeds as much as the Monarch and Queen butterflies, and they exist together as part of the natural ecosystem. Although their common names are similar, large and small milkweed bugs differ in more than size.

Large milkweed bugs (LMBs) are herbivorous – they feed on the leaves, stems, and seeds of milkweed using their long proboscis. In general this is not harmful to the milkweed plant, although if there is a large population boom, LMBs can stress the plant and cause misshapen seeds and lower seed production.

Large Milkweed Bug: note the black band across the wings and red face mask

Small Milkweed bugs (SMBs) are mostly herbivorous, but can occasionally be scavengers. These insects have been reported feeding on a wide variety of other insects, such as honey bees, monarch caterpillars and pupae, and dogbane beetles. While it may be disappointing to see monarch eggs, larvae or pupae preyed upon, this is all part of a vibrant milkweed ecosystem, and this predatory behavior is likely most common when their preferred food source is scarce.

Small Milkweed Bug: note the reddish-orange pattern forms an “X”

Milkweed bugs protect themselves by ingesting, then storing, cardiac glycosides from the milkweed, and as a result don’t have an issue with natural predators. The reddish-orange coloration is a warning to predators to stay away.

So should you be concerned about milkweed bugs in your garden? In general, no, they are part of the balanced ecosystem. However, if there is a large population boom, you may elect to reduce feeding pressure by culling some of the bugs, although this is a contentious subject 😉


The potential consequences of ‘bee washing’ by Sheila R. Colla (2022)

Over recent decades, the plight of wild bees and other pollinators has gone from a niche area to one of the most mainstream environmental topics. Scientific research interest, capacity and consequently publications have grown tremendously in recent years, as has mainstream media coverage. The public has been engaged in a variety of ways to “save the bees” including through community science, policy consultation, planting of pollinator gardens and other widespread initiatives and campaigns … ‘Bee washing’, a term coined by MacIvor and Packer (2015), refers to items or actions claiming to support declining bee populations, and thus claiming to be pro-environment, without due diligence or scientific support … The crux of the matter is that when conservation actions are misplaced, as in the case with bee washing, they can actively harm populations meant to be conserved, waste limited resources (e.g. time, energy, money), misinform the public and/or de-legitimize scientific evidence.

Excerpts from Colla, S. R. (2022). The potential consequences of ‘bee washing’ on wild bee health and conservation.

To read more, visit or the International Journal for Parasitology: Parasites and Wildlife, 18, 30–32

Native bumblebees may be threatened by “pathogen spillover” from managed species

In order to better protect wild bee health and biodiversity, conservation actions and policy will have to shift away from bee washing to more evidence-based, nuanced and precautionary approaches. Efforts should focus on reducing the reliance of systems on managed bees and reducing the impacts of managed bee use on wild bees. This will require policy which acknowledges and values the importance of wild bee health biodiversity for pollination services for crop plants and for resilience under climate change. Critical actions to protect wild bee health includes screening and monitoring of pathogens among commercial stock and in adjacent wild populations.

Excerpt from Colla, S. R. (2022). The potential consequences of ‘bee washing’ on wild bee health and conservation.

On Farming Metal From Plants and Intelligence Beyond Humans

Basking in our industrial and technological successes, humans have proudly flaunted their superiority over the natural world. But now the true cost of that hubris is coming to light – is it too late?

The answer will likely only make itself available in hindsight, but it’s not too late to learn.

In James Bridle’s Guardian article we a glimpse through the clouds at natural intelligence that has surrounded us, unnoticed until relatively recently. Read the story here.

There is so much intelligence on this planet other than ours. Realising that will be key to adapting to climate breakdown.

If we can farm metal from plants, what else can we learn from life on Earth? James Bridle

And how a slime mold, which is a creature somewhere between fungi and amoebae, can solve the “traveling salesman” problem faster than any supercomputer. The problem at hand: A salesman must visit n cities, going to each city only once, and then return to their starting point — what is the shortest possible route that they can take? Read the Science News article here.

And how cows, sheep and dogs appear to anticipate earthquakes better than any sensor or algorithm. Read the Scientific American article here.

And the octopus, whose distributed nervous system illustrates a different way of thinking. Read the Scientific American Mind article here.

Or how about spiders offloading cognitive tasks to their webs? Read the Quanta Magazine article here.

And not to leave out our often overlooked neighbors, how plants talk to each other through their roots. Read the Guardian article here.

One Year in my Pollinator Garden

Painted Lady visits apple blossoms (Vanessa cardui on Malus domestica)

I joined iNaturalist in April 2021 to participate in the City Nature Challenge – 2022 edition is coming up soon! – and I had no idea at the time that it would be my go-to resource for appreciating and documenting the visitors in my pollinator garden. I was quickly drawn in by the many friendly and knowledgeable users and the potential to improve my understanding of the natural world. One year later, I’m delighted to reminisce and share highlights from my edible garden and native plant xeriscape. It has been a blast watching, photographing, and learning to identify hundreds of species of plants and animals. Please, join me for a celebration of diversity in my New Mexico neighborhood.

3 varieties of sunflowers (Helianthus) blooming in summer 2021

Getting Started

My journey to hosting a pollinator garden in Albuquerque began with an all but blank slate. The front yard was a sea of bare gravel plus cheatgrass, tumbleweeds, and goatheads, while the back featured 8 Russian olive trees and plenty of dandelions. In 2020, I decided to transform the landscaping and hired a local company to cut down the invasive trees. In their places, I planted Peach and Apple trees for fruit, Utah serviceberry (Amelanchier utahensis) and New Mexico olive (Forestiera pubescens) to feed songbirds, and Bigtooth maple (Acer grandidentatum) for shade and fall color. Thanks to the New Mexico Native Plants Society, Plants of the Southwest, Osuna Nursery, Hilltop Landscaping, the American Penstemon Society, and the ABQ Backyard Refuge Program, I found plenty of resources and support to select appropriate, drought-tolerant plants for my yard and begin to create habitat for wildlife.

Habronattus festus jumping spider

Watching the Grass Grow

At the beginning of the project, I typically saw common city birds, lizards, bumblebees, rock squirrels, paper wasps, and not much else. It takes a while for new plants to get established and for neighborhood critters to (re)discover my yard. It’s all worth it now for moments like watching an American Robin eat serviceberries, a longhorn bee sleeping on a sunflower, or munching on a fresh apple that I grew.

Large-tailed Aphideater (Eupeodes volucris hoverfly) on Arugula

When I started, I was familiar with common pollinators, like honeybees and hummingbirds, but there were so many branches of the Animal kingdom of which I wasn’t aware. (I’m doing a little better now and I hope you’ll scroll through some of our visual guides Insects – Pollinator Web.) By slowing down and observing with purpose, I find something new in the garden almost every day. It is both fun and frustrating to follow a little bee on her journey to collect pollen as I struggle to get clear pictures for identification.

Tripartite Sweat Bee on Scorpionweed (Halictus tripartitus on Phacelia integrifolia)

By The Numbers

Honestly, I have been blown away by the diversity that can exist in 0.2-acres of land. We tend to think of deserts as arid and empty; in reality, Arizona and New Mexico combined have over 1,000 species of native bees plus more than 300 species of butterflies! I have recorded more than 600 yard species in the last 12 months, using iNaturalist. They include:

  • >100 species of cultivated plants, including 20 varieties of native trees and shrubs
  • 75 bees
  • 59 butterflies and moths
  • 59 birds
  • 58 flies
  • 50 ‘true bugs’ (Hemiptera)
  • 47 volunteer plant species (“weeds” and wildflowers introduced by wind or animals)
  • 45 wasps
  • 37 beetles
  • 21 spiders
  • 12 crickets, grasshoppers, and katydids
  • 11 ants
  • New Mexico Whiptails and Southwestern Fence lizards
  • Flame Skimmer and Blue-fronted Dancer (dragonflies)
  • 2 springtails
  • 1 mayfly!
An unexpected mayfly showed up as I was leaving for work last year

Closing Thoughts

Imagine what we can do working together in our communities by planting yards full of flowers, instead of spraying chemicals and mowing lawns.

Every square inch of planet earth has ecological significance, even where we live, work, and play. If we landscape these areas with plant function as well as aesthetics in mind, we can create viable habitat where humans are, not just where humans are not … Today’s environmental challenges are so enormous that it is easy to feel helpless, as if one person can’t make a difference – despite the cliché that suggests you can. In this case, however, the cliché is right on: by choosing ecologically-effective plants for your landscape, by shrinking your lawn, and by removing your invasive ornamentals – all actions a single person can take – you will be able to make a difference that you can see, and enjoy, almost immediately. Life will return to your property!

Quote from Doug Tallamy
Lewis’ Soldier Beetles were abundant in fall 2021 on snakeweed, goldenweed, and Chamisa

Glamorous Moths #4 – Southern Flannel Moth

Wide ranging across the southern USA and northern Mexico, the Southern Flannel moth, Megalopyge opercularis, is this week’s featured moth. Read more here, if you’re interested: Megalopyge opercularis ( Flannel moths are in Superfamily Zygaenoidea with Jewel Caterpillar moths, like Dalcerides.

Male Megalopyge opercularis by Judy Aschner on

It’s larval food plants are mostly oak trees and some Manzanita species in Arizona and Mexico. The caterpillar is small and hairy like adults and it would be really cool to find one in the wild, so please let us know if you see any!

Southern Flannel caterpillar by Diana Foreman on

The Ladies and a Gentleman

Painted Lady, American Lady, West Coast Lady and Red Admiral Butterflies

Brush-footed butterflies belonging to the genus Vanessa, the name of the genus may have been taken from the character Vanessa in Jonathan Swift’s poem “Cadenus and Vanessa,” which is the source of the woman’s name Vanessa. In the poem Vanessa is called a “nymph” eleven times, and the genus is closely related to the previously-named genus Nymphalis (Wikipedia).

Painted Lady

The Painted Lady, Vanessa cardul, is the most widespread of all butterfly species, and, like the Monarch, has an amazing migratory story to tell.

Distinguishing features include 4-5 submarginal spots on the underside of the wing, and a white outline at the outer edges of the top of the wing near the white spots.

Larval host plants include Arizona Thistle, Desert Cotton, Globemallows, Western Betony, Mexican Sunflower Bush, Yarrow and Western Mugwort. Adults feed on nectar.

Males perch on shrubs or hilltops and patrol for females. Females are generally larger than males.

Females lay eggs singly on the top of host plant leaves. Caterpillars are solitary, living and feeding in a nest of leaves tied with silk. Adults hibernate in mild winters.

West Coast Lady

The West Coast Lady, Vanessa annabella, are the least ranging of the Vanessa species in the continental U.S. In fact, it’s typically limited to the Western part of the country.

Distinguishing features include an orange patch at the top outer edge of the wing on the top side and 4-5 submarginal spots on the underside.

Larval host plants include Globemallows, Hollyhocks and other plants in the mallow family. Adults feed on nectar.

Males perch to watch for receptive females. Females lay eggs singly on upperside of host plant leaves; caterpillars eat leaves and live in a silken nest. Adults hibernate.

American Lady

The American Lady, Vanessa virginiensis, reside in the Southern United States and temporarily colonize the northern states.

Distinguishing features include two large eye spots on the underside of the wing, and a white spot in the orange field on the topside of the wing.

Larval host plants include Globemallows, Western Mugwort, Sonoran Everlasting and Groundsel. Adults feed on nectar.

In the afternoon, males perch on hilltops or vegetation to patrol for females.

Females lay eggs singly on the top of host plant leaves. Caterpillars are solitary, living and feeding in a nest of leaves tied with silk. Adults hibernate.

photo by justmarys on iNaturalist

Red Admiral

The Red Admiral, Vanessa atalanta, is wide ranging from Mexico up to Canada, but cannot survive cold winters so most of the northern U.S. is recolonized each spring by southern migrants.

Markings are quite easy to distinguish from the Ladies. Red admirals are territorial; females will only mate with males that hold territory. 

photo by burkardleitner on iNaturalist

Larval host plants include New Mexico Hops and plants in the nettles family.

The Red Admiral has a very erratic, rapid flight. Males perch, on ridgetops if available, in the afternoon to wait for females, who lay eggs singly on the tops of host plant leaves. Young caterpillars eat and live within a shelter of folded leaves; older caterpillars make a nest of leaves tied together with silk. Adults hibernate.


Meet the Plants: More Beardtongues

Common southwest species include Beardlip/Scarlet bugler (top row, 2nd from left), Palmer’s beardtongue (top, 3rd from right), and Rocky Mountain beardtongue (bottom row, 2nd from right).

I previously shared a few common garden Penstemon in this post. Yesterday, I was watching a talk on Penstemon by Dr. Andi Wolfe (Ohio State University) and she has some beautiful slides. Please enjoy this look at Penstemon diversity.

The shape and size of Penstemon flowers varies dramatically. Top row, second from the left, is Penstemon barbatus, a common wild and garden plant in Arizona and New Mexico.
Botanists use the anthers (male reproductive organs) of Penstemon flowers to classify species.
In the bottom of most Penstemon flowers is the staminode aka beardtongue. One theory states that this provides a landing platform for bees to enter the flowers.

Glamorous Moths #3 – ‘Colorado’ Yucca Moth

This is the third post in a semi-regular series of interesting, colorful, and unique moths of Arizona and New Mexico. Today, I’d like to introduce you to yucca moths.

Prodoxus coloradensis © BJ Stacey on

Yucca moths are in the Family Prodoxidae and found across the USA and Mexico. They are a spring and summer moth, timing their flights with blooms of different plants in the Agave family (Asparagaceae). Prodoxus coloradensis is found from southern California to West Texas and north along the front range of Colorado. It’s black stripes are a bold contrast to many plain, white yucca moth species.

Yucca moth caterpillar © Bill Harms on

Like all desert blooms, Joshua trees depend on just the perfect conditions: well-timed rains, and for the Joshua tree, a crisp winter freeze. Researchers believe that freezing temperatures may damage the growing end of a branch and stimulate flowering, followed by branching. You may notice some Joshua trees grow like straight stalks; these trees have never bloomed—which is why they are branchless! In addition to ideal weather, the pollination of flowers requires a visit from the yucca moth. The moth collects pollen while laying her eggs inside the flower ovary. As seeds develop and mature, the eggs hatch into larvae, which feed on the seeds. The tree relies on the moth for pollination and the moth relies on the tree for a few seeds for her young—a happy symbiosis. 


The Gulf Fritillary Butterfly

The Gulf fritillary or passion butterfly (Agraulis vanillae/Dione vanillae) is a bright orange butterfly in the subfamily Heliconiinae of the family Nymphalidae.

Females are generally larger and have more brown in their markings. Gulf fritillaries have a chemical defense mechanism in which they release odorous chemicals in response to predator sightings. As a result, common predators learn to avoid this species.

Gulf Fritillaries have several broods in spring and summer, and can survive winter temperatures as low as 21 degrees F. Adults overwinter.

Favorite nectar plants include Lantana, Butterfly Bush, Zinnia, Aster and Thistle.

Yellow eggs are laid singly on or near some species of Passion Vines like Maypops (Passiflora incarnata), Passiflora lutea and Passiflora affinis. Eggs gradually turn a brownish-red color.

Left: A Gulf Fritillary nectaring on Lantana

Suitable host plant species provide a good structure for larval host habitats which enables young populations of gulf fritillaries to be sufficiently nurtured and protected.

The driving factor behind what causes the female to oviposit on or near the host plant is most likely due to the certain chemical composition of the specific genus of the host plant. Once the female recognizes the chemical composition (by using the antennae), the female will oviposit.

Larvae may feed on all parts of the plant and can rapidly defoliate host vines.

Right: Caterpillar on Bluecrown Passionflower (Passiflora caerulea)

Gulf Fritillary and chrysalis

When the caterpillar is ready to create a chrysalis, it turns a grayish color and begins to spin a silk-like ball that it uses to attach to a surface.

The pupa is mottled brown and resembles a dead leaf.

Egg stage – 4 to 8 days
Caterpillar – 2 to 3 weeks
Chrysalis – 5 to 10 days
Butterfly – 2 to 4 weeks


Butterflies at Home

University of Florida