News From the FrontWhat’s going on in the world

of Monarch science

It’s a battle zone out

there!

The new numbers are out

What Affects Overwintering Numbers?

Season they are measured!—doesn’t change population, but does change results

Weather conditions in the summer breeding range—winds, drought, floods, cold, heat

Milkweed and nectar availability along their northbound route and in the summer breeding grounds

Success of overwintering group the previous year—storms, winds, wet + cold, OR, cool dry but not too dry conditions with occasional warm days

Availability of nectar for fattening up migratory generation

Monarchs have the “Goldilocks Syndrome” and need everything juuuuust right!

Not everything you read, see or hear has been well researched

• One reporting error can lead to a bad information cascade• Hurricanes—do have some effects (Earl, Maine, 2010)• There is no actual evidence that any of the hurricanes that

impacted the North American continent in 2017 (four of them) hit in the right places at the right times to seriously reduce Monarch populations. Coastal year-round populations (Houston, Galveston)are more of a population sink than booster.

• News sources in 2017 largely repeated the words of one reporter, who, in the opinion of the actual interview subjects, misrepresented their statements completely.

Scent patch research

Closeup of the Androconial Patch on a male Queen butterflyPhoto by David Millard

LBJ Wildflower Center

Wrapped up milkweed growing project—funding cycle ended. Produced a procedure and guide to growing milkweed seeds.

Produced a pocket guide to buying Monarch plants, designed to be taken to the nursery called ‘Power the Migration—A Pocket Guide To Texas Plants For Monarchs’

Using butterfly anatomy to catch one

• Butterflies see very differently during different stages of their lives. Larval vision is limited and poor. They see through their 12 simple ocelli, which have only a couple cells each. Adults have compound eyes made up of thousands of ommatidia. Each ommatidium gathers light and processes visual information through its own lens and nerve system.

• Compound eyes give butterflies excellent perception of color and motion in a wide range; butterflies can see up, down, forward, backward, and to the sides at the same time. On the other hand, they are not very good at judging distance or perceiving patterns, and the images are not united into one continuous picture. Butterflies apparently see the world as a series of still photos rather than a movie. Therefore, they often fail to detect slow steady movement.

Just Breathe!

Forcible mating—exploding monarchs?

• Monarch females will often receive more than one male—the last male actually gets to fertilize the eggs

• Males impart a nuptial gift of lipids, carbohydrates, defense chemicals and proteins—up to 10% of male’s body weight (spermatophores)

• There have been recent reports of female monarchs bursting at the overwintering grounds where they have been forced to mate too many times.

• Even though researchers have many breeding age monarchs in breeding cages, this has only very rarely been observed in those situations, so is likely rare in the wild as well.

• Monarch females can, in fact, employ several different strategies to avoid mating.

Fire Ants• Good news! According to one study, Red

Imported Fire Ants do not appear to be a major predator of Monarch larvae. It was feared that they were, but recent studies show they might not be the big problem we thought they were.

• Scientists studied “fire ant excluded’ and “fire ant enhanced” zones around milkweed with eggs.

“5th Generation” from Texas and Oklahoma

• Kristen Baum, from Oklahoma State University has been studying this topic.

• Fall milkweed up to 17% the density of Spring milkweeds in TX and OK

• Late instars peak around Sept 11-17,• Most will emerge as adults right around September

30th—also peak migration for much of Oklahoma• Fall caterpillars seem to have higher, sometimes much

higher, rates of parasitism by flies.• Some 5th generation tagged Monarchs have reached

Mexico.

Photo by Stephanie Jennings

Virtual fencing for cows

• How it works

Mayor’s Monarch Pledge

Project Monarch Health –University of Georgia, (Sonia Altizer)

Monarch Health is a citizen science project to track the prevalence of the protozoan parasite Ophryocystis elektroscirrha (OE)

There is year to year variation in the prevalence of OE infection

OE infection reduces capacity to feed (some cannot eat due to defects), fly, lay eggs, and reduces lifespan

OE prevalence not strongly correlated with overwintering numbers

OE very strongly correlated with non-migratory populations. If they fail to migrate, unwell individuals aren’t culled naturally. Disease continues to increase as infected Monarchs stay put it the area leaving “spores” behind on plants where caterpillars ingest them.

Prevalence has tripled in the last decade in eastern migratory Monarchs

Sam Houston State (Will Godwin)

Doing research on OE.

First year study: looked at archived specimens, larval fitness

They found 38 out of 51 (76% ) of the Monarchs tested in Houston to be OE positive. Not surprising considering the number of Tropical Milkweeds planted there. Prevalence is at least 5X higher in winter breeding populations like those in Houston.

They will next test for OE in:Overwintering groundsHaymeadowsMuseum specimensLive specimens

They are also dissecting infected specimens to see how OE affects different body parts.

Butterflies migrating north from Mexico don’t find substantial milkweed numbers until they reach Central Texas if they come up the middle of Texas. There is more near the coast.

Isotopic studies under way—currently using Hydrogen and Carbon

Xerces/USDAThe Western Monarch population has fallen by over 85% two years in a row, following previous declines. There is a pretty good chance they will be gone in 50 years. The number of overwintering sites in California at which Monarchs are counted keeps going up, but the numbers of butterflies have remained low.

Field Museum, ChicagoThey have hired a cultural anthropologist to study how to get people to respond to the problem.

Her approach is “asset based”—focused on what we do have rather than what we don’thave.

They are using technical tools to assess available spaces that are underused

Usual obstacles to getting people to plant more habitat on their plantable spaces:Time, money, information, access to seeds, traditional aesthetics.

Her suggestions: Tailor the message. Engage different kinds of landowners with different messages.

They have created the Urban Monarch Conservation Guidebook , found buried under some tabs at www.fieldmuseum.org. *best found by searching the site with the search function)

Seed AvailabilityTexas Native Seeds Project

Catch 22: supply and demand must arrive balanced, at the same time, for the economics to be viable.

There has been a strong demand for wildflower seeds for restoration projects, but no supply for many species. On the other hand, large scale growers won’t embark on growing seeds unless the demand is large enough to make it profitable quickly. The Texas Native Seeds Project, now working in several regions, seeks to bridge the gap and develop new sources of seeds by providing seeds to farmers to be grown out for seed increase under exacting conditions.

Desert Botanical Garden--Phoenix, Arizona4 milkweed test

Queen caterpillars were evenly distributed across all four test species

Monarchs were strongly attracted to one species of the four. (Asclepias subulata)

Honeybees preferred Asclepias linaria

77% of all the eggs laid were laid on plants with aphids. Aphids do not discourage Monarchs from laying eggs, and might even encourage selection.

Navigation—where they come from and go to

“Time compensated sun compass”

Flight simulator

Simple graph indicating three test subjects engaged in directional flight to the Southwest

N

Monarchs can still tell which way to go when it’s cloudy

• Polarized light detection—circle flight observed in the rain in Oklahoma

• Magnetic compass—antennae are magnetosensors with the help of a compound called “cryptochrome”

Amazing Antennae

clock cells

light mediated radical pair reactions

olfactory sensors

wind sensors

temperature sensors

Why do Monarchs change migration direction?

• Not changing day length--experimentally

• Need cold weather (approximately 24 days) to reset compass and head North—again experimentally

• What causes the shift at the other end of the migration, when they start to head back South, may be day length shifts, change in temperature, sun angle shifts, declining resources, a combination of factors, or something else.

Arizona Monarchs—Gail Morris, Southwest Monarch Project

• Some Arizona Monarchs travel to Mexico

• Some actually cross the mountains and end up in California. Depends largely on timely winds.

• The proportion of monarchs doing each varies year to year

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TASTE & SMELLButterflies have chemical receptors scattered across their bodies.

These chemoreceptors react to the presence of different chemicals in the environment. For example, organs on the back of butterfly tarsi (feet) sense dissolved sugar; when the dissolved sugar touches these chemoreceptors, the butterfly extends its proboscis to eat the nectar its tarsi have sensed.

Adult butterflies sense most smells through their antennae, which are densely covered with chemoreceptors, especially on the clubs. In monarchs, chemoreceptors on the antennae sense the honey odor associated with nectar and feeding as well as special chemicals released by the male, called pheromones.

Female butterflies often have important chemoreceptors on their legs to help them find appropriate host plants for their eggs. These chemoreceptors are at the base of spines on the back of the legs, and they run up along the spine to its tip. Females drum their legs against the plant, which releases plant juices. The chemoreceptors along the spines tell the butterfly whether they are standing on the correct host plant. Monarch females test host plants with all six legs before laying eggs.

Monarch Butterfly Fund underwrites kitchen gear!

Fuel-saving stoves help save Monarchs in the area of the Mexican overwintering grounds by keeping the number of trees cut for fuel to a minimum. Excess tree cutting in the reserves cause changes in the microclimate within the forests there.

Monarch Butterfly FundCash Prize

• Cash prize of $50,000 for a system that can tag and track a migrating Monarch for their whole journey.

Monarch Butterfly Fund

• They are studying and trying to facilitate the “assisted migration” of Oyamel Fir forest UPthe slopes of the mountains. They are concerned about climate change and warming temperatures leaving the current forest too hot for Monarchs. Monarchs that don’t get enough chill time won’t migrate North.

Bring Back the Monarchs to Texas• Recently awarded 16 grants totaling about $6,000,

for Monarch gardens featuring native plants in Texas• Participating in regional “Train the Trainer” seminars

with National Wildlife Federation• Unveiling new initiatives soon

– Regional plant lists for Texas– Regional Monarch Waystation plans

• TPW would like to see easily digestible information that is regionally specific and step by step—Master Naturalists and NPSOT can help

How you plant it matters• Garden design –no big clumps of

milkweed…research based recommendations• John Pleasants’ studies have shown that female

Monarchs naturally prefer to lay eggs spaced widely apart.

• Predators have an easier time finding eggs and larvae when milkweeds are planted in blocks or rows.

• Closely spaced milkweeds may also facilitate the spread of disease and parasites.

Chip Taylor, Founder of Monarch Watch on the state of Monarch science:

Many models of Monarch behavior are based on linear regressions, even though actual responses to change are non-linear, with no reason to expect them to be linear. Current models are inadequate to predict Monarch populations or behaviors. Annual weather features drive much of Monarch behavior, including the year to year variations in their density in certain regions.

“This will be the most studied animal ever. We will study it right to its extinction.”

What we need is immediate action without waiting for the data to determine which nectar plant is most nutritious. The no harm/no foul action that can be taken now is to plant lots of flowers and milkweeds—everywhere we can.

Our job is to help nature be as resilient as possible—

there is no finish line.

Karen Oberhauser

McKinney took the Mayor’s Monarch Pledge

• 10 out of 24 suggested activities pledged. Mayors who decide to take 8 or more actions will receive special recognition and become a member of the Mayors' Monarch Pledge Leadership Circle

• Many cities choose just 3 activities

• Program of National Wildlife Federation