In some plant species, bees must vibrate the flowers to shake pollen loose. The technique is called buzz pollination or sonication.
Buzz-pollinated plants have anthers with very small openings so the pollen stays inside unless the anther is shaken. To collect the pollen bees grab the flower and vibrate their flight muscles. This makes a buzzing sound.
In the photo above, a halictid bee is releasing yellow grains of pollen as she shakes. She collects it on her legs for delivery to the hive.
Most species in the Solanum genus, including potatoes, eggplants and tomatoes, have to vibrate to release their pollen. Strong wind can do the trick outdoors but greenhouse tomatoes are out of luck. That’s how bumblebees get an indoor job.
(photo from Wikimedia Commons; click on the caption to see the original)
In June 2012 just before Tropical Storm Debby began to spin off of Florida’s Gulf coast, scientists tagged a loggerhead sea turtle with a GPS tracking device. Nicknamed Eleanor, she laid eggs on the beach and returned to the sea near Sarasota. Then the storm arrived.
Would the storm hurt Eleanor? They watched her for clues.
Before the storm Eleanor saved energy for her next egg-laying excursion by resting on the seabed and only moving when she surfaced for air.
When Tropical Storm Debby arrived, Eleanor was caught in it and swept north by its current. The storm churned for four days with sustained wind speeds of 65 mph. Eleanor was active the entire time.
Instead of resting she swam, dove, and surfaced. Amazingly, this used no more energy than she would have expended on producing 2% of her next set of eggs. Meanwhile the storm pushed her 62 miles (100 km) north of her nesting beach.
The study concluded that tropical storms don’t pose much risk to adult sea turtles like Eleanor.
Unfortunately, as researcher Maria Wilson pointed out, “Sea turtle nests are extremely vulnerable to passing storms. The storm that Eleanor easily survived destroyed almost 90% of nests on the beach where she and several hundred other female turtles had laid their eggs.”
The study concluded that when it comes to protecting seas turtles we should focus on protecting nests and helping newly hatched turtles. We don’t need to worry about the adults. They can ride out the storms.
In the American West there’s a 3-inch long katydid called a Mormon cricket (Anabrus simplex) that cannot fly but it sure can walk.
We hardly notice Mormon crickets until millions swarm and march across the landscape, advancing more than a mile a day like a Biblical plague of locusts. Naturally scientists wondered what makes them do it.
A 2006 study discovered that the swarms are driven by hunger and fear. The crickets are hungry for protein and salt so they start to migrate, but the bugs are cannibals and will eat each other if they can. Those at the back of the pack pursue the front line to catch and eat them. Fear forces the crickets to keep track of their neighbors and constantly on the move.
Despite the danger from behind, individuals sometimes double back into the crowd. If enough of them do it the whole swarm changes direction. How does this happen? What signals such a change?
We concluded that the mechanism through which locusts agree on a direction to move together (sometimes with devastating consequences, such as locust plagues) is the same we sometimes use to decide where to live or where to go out: we let ourselves be convinced by those in our social network, often by those going in the opposite direction.
We don’t necessarily pay more attention to those doing the same as us, but many times [we pay more attention] to those doing something different.
But what happens when there are no monarchs or queen butterflies around and the local predators learn that viceroys are safe to eat? The viceroys change their tactics.
A 15 year study in northern Florida — where queen butterflies don’t live — found that in the absence of queens the viceroys retain a chemical in their bodies that makes them taste sour. Thus they aren’t eaten. In fact they thrive.
If you keep honeybees in the Pittsburgh area, you’ll want to be sure your hives have not caught a highly contagious and deadly disease — American foulbrood (AFB).
This summer a beekeeper in the city of Pittsburgh suspected there was something wrong with his hives so he called for help from PA Department of Agriculture’s Apiary Inspectors, Bonnie Hall and Ken Hoover. On 5 July 2019 they found that six of his colonies had American foulbrood (AFB), the most widespread and deadly of bee brood diseases. Because AFB is so contagious, the inspectors checked all the registered hives within a 2.5 mile radius of the incident. They found more AFB in Pittsburgh and expanded the alert zone.
Adult bees unwittingly carry foulbrood spores into the hive and feed infected food to their young. When the larvae die the bacteria generates millions of spores that are spread easily by bees and beekeepers. The spores remain viable for up to 80 years even when exposed to extreme weather, antibiotics and disinfectants. Burning the hives and irradiating your equipment is the only way to kill the spores.
As of 29 August 2019, all or part of the following Pittsburgh neighborhoods are within the American foulbrood alert: Bloomfield, Garfield, Central Lawrenceville, Stanton Heights, Friendship, Shadyside, East Liberty, Larimer, Point Breeze North, Point Breeze, Squirrel Hill North, North Oakland, Squirrel Hill South, Hazelwood, Glen Hazel, Greenfield, South Oakland, Spring Garden, Spring Hill (City View, Northside), Fineview, Perry South, Northview Heights, East Allegheny, and Troy Hill.
I have colored a neighborhood map of the city with red to give you an idea of the scope. Note that my map is not as accurate as the list of neighborhood names.
Foulbrood alert in these Pittsburgh neighborhoods (colored red), August 2019 (map from Wikimedia Commons, colored by Kate St. John)
Help stop this deadly honeybee disease!
If your bees are in the alert zone, make sure your hives are inspected for AFB. Contact State Apiarist Karen Roccasecca (717-346-9567 kroccasecc@pa.gov ) or local inspector Bonnie Hall (717-956-8175) to schedule an inspection.
If you have questions, contact State Apiarist Karen Roccasecca (717-346-9567 kroccasecc@pa.gov ).
If you have not registered your beehives the inspectors won’t know about them. For the health and safety of all honeybees, it’s important to register your hives! (It’s also required by state law since 1921.) Use the Mail-In Registration Form or Online Registration.
No need to worry about the honey. Karen Roccasecca says: “Please note that American foulbrood does not affect humans and the honey is safe for human consumption.”
Note: Direct quotes, where origin not is stated in the text, are linked to the source material.
(photos and map from Wikimedia Commons; click on the captions to see the originals)
In the past week I’ve noticed many monarch butterflies in flight and they’ve all been heading south.
When you see a monarch, pay attention to the direction it’s heading. Right now is the peak period for them to pass through Pittsburgh on their way to Mexico.
Monarch butterflies are on the move!
(photo from Wikimedia Commons; click on the caption to see the original)
Who knew that millipede bodies move vertically as they walk? Who knew that their antennae tap in time to their steps?
Diplopoda or millipedes are a class of 12,000 arthropods with two pairs of jointed legs on most of their body segments. Though mille means a thousand, Wikipedia says that none of them have that many legs. The record is 750.
Millipedes are susceptible to drying out so they live where it’s cool and moist, especially under leaf litter. They’re active at night but you might see them at dusk or on a very damp day when they come out to forage for decaying leaves, decaying plants or fungi.
They can’t bite or sting so their only defense is to curl in a ball and, when really irritated, release a stinky liquid.
At certain times of the year millipedes become restless and migrate from their normal living places; they [may] appear in window wells, basements, garages and other places where they become an annoyance.”
This restlessness usually has to do with mating. The crowd was looking for a cool damp place and made a mistake.
Don’t be alarmed. It’s too dry for them indoors. Penn State says, “Since millipedes do not live for more than a few days indoors, treatment inside the home is not necessary. Vacuum or sweep millipedes into a dust pan for removal.”
Of course, you’d have to get really close to a millipede to see this.
I’m not ready for that yet.
(photos from Wikimedia Commons; click on the captions to see the originals. Video shared on Twitter by @DickKingSmith; video originally by Crystal Albright a.k.a. Chris Dull on FB)
p.s. The photos in this article are of a single species found in eastern North America, the American “giant” millipede, Narceus americanus. I’ve seen them in Pennsylvania.
This moth can remember what it learned as a caterpillar.
In 2008, scientists at Georgetown University exposed late-stage tobacco hornworm caterpillars (Manduca sexta) to a specific scent and trained them to avoid it with a mild shock. The caterpillars got the message.
Scientists had thought that metamorphosis changed the brain so much that moths would not remember their caterpillar past. However, the caterpillars that learned about the scent in their last instar remembered the scent when they became moths — and they avoided it.
I wonder if other butterflies and moths remember their final days as caterpillars. Perhaps this is how females know to lay eggs on their host plant. “Hmmm,” says the butterfly, “This smells like the plant where I was feeding before I could fly.”
A long slender beak-shaped mouth part (proboscis) for sucking liquid food.
A partially hardened pair of front wings with clear tips and completely clear rear wings shorter than the front ones.
Few joints in the antennae and feet: antennae about five joints, feet usually no more than three.
Cicadas have these characteristics so they and 50,000 to 80,000 other insects are in the “true bug” Order Hempitera. This tiny green flatid planthopper is too.
Flatid planthopper hiding on a bottlebrush buckeye stem in Schenley Park (photo by Kate St. John)
But their status is more complicated. These two are true bugs but not true “True Bugs.”
Within Hempitera there’s a suborder of really True Bugs called Heteroptera. Cicadas, planthoppers, spittlebugs, aphids, and adelgids aren’t in this suborder. (See taxonomic chart from bugguide.net below.)
This green and brown shield bug (probably Elasmostethus artricornis) is native to North America. I found several perched on American spikenard in Schenley Park.
A true bug, probably a shield bug (photo by Kate St. John)
The invasive brown marmorated stinkbugs are mating this month. I found this pair at Washington’s Landing.
Brown marmorated stinkbugs mating (photo by Kate St. John)
And finally, I think this is a leaf-footed bug because of the swollen leaf-like segments on his hind legs.
Leaf-footed bug (photo by Kate St. John)
Wondering if a bug is true? It’s a safe bet that it isn’t. Most insects are not true bugs, including dragonflies, bees, wasps, grasshoppers, butterflies, moths, flies and fleas.
Eastern monarch butterflies, famous for their autumn migration from North America to Mexico, have declined 80-90% in the last 20 years. To help the butterflies many people collect eggs and caterpillars in the wild and captive-raise them to increase their chances of survival. Unfortunately this well-meaning act can damage the insect’s ability to migrate.
Researcher Ayse Tenger-Trolander at Univ. of Chicago stumbled upon this when she purchased captive-bred butterflies for her monarch migration study. To measure their autumn migratory drive she placed them in a flight simulator and noted the dominant direction they wanted to fly. Wild migratory monarchs orient South. The captive-bred monarchs chose random directions, unlikely to migrate.
To further test the butterflies, Tenger-Trolander collected wild monarchs and raised a new generation indoors, mimicking outdoor autumn conditions. Here’s what she found.
Furthermore, rearing wild-caught monarchs in an indoor environment mimicking natural migration-inducing conditions failed to elicit southward flight orientation. In fact, merely eclosing(*) indoors after an otherwise complete lifecycle outdoors was enough to disrupt southern orientation.
Chip Taylor, Director of Monarch Watch, pointed out on NPR that some captive-bred monarchs do make it to Mexico, but added that “The real reason for raising monarch butterflies is for the enjoyment, the education. [T]he idea of individuals saving caterpillars as “monarch rescue” is misguided. “That’s simply not going to work as a way to boost the population,” says Taylor. “What we really need to do is to improve the habitat.”
We’re learning that monarch migration is complex and very fragile. It’s easy to break it in a single generation.
