Friday, April 26, 2013

Hidden Wren

Carolina Wren- Wikimedia
The last few weeks we have been hearing this shrill call in the trees off our deck. We and our friends scanned the trees but although they hadn't leafed out yet, we could never locate the bird. Finally in desperation I made this recording of the song and sent it off to friends in Audubon. Each responded that it was a Carolina Wren.
Lisa Berger explained our failure to see the bird. We were searching the high tree tops where we thought the sound was coming from. In addition to being small, the wren wasn't that high.
"Human ears are good at discerning sound direction horizontally, but not so great vertically. Humans all interpret this as a shortcoming, and it can make us feel insane. Universally we all suffer from it.
You recorded a male Carolina Wren's song. While these guys can travel and sing about anywhere in two dimensions, they are most often found less than 8 feet off the ground. This is mid season for their first brood, so watch for them carrying food to the nest."
Carolina Wrens are sedentary--don't migrate, and are one of the few species here that maintains their territory year-round, with males singing all year. Listen for the females, who combine a buzzy, melodic trill (pair, synchronous or duet sing) with the male's song." (see Cornell's avian duetting link)
The recordings we found on line didn't match with what we were hearing.  Again, Audubon to the rescue.  Jan Horton described this call as "one of his many songs, jiminy jiminy jiminy jun.  Another is teakettle, teakettle, etch." 

There is a lot of regional dialect in birds, and, really, only a few recordings for each species.  According to allaboutbirds.org,
"Only male Carolina Wrens sing—a series of several quick, whistled notes, repeated a few times. The entire song usually lasts less than 2 seconds and the notes are usually described as three-parted, as in a repeated teakettle or germany. Each male has a repertoire of up to several dozen different song variations. He'll sing one of these about 15 times before changing his tune."
Notice the "his"- only the male wrens call.  Barb says that being loud and repetitive like my recording above is a male trait which has been passed on to higher species of bipeds.  I think I may be hurt.

Wednesday, April 24, 2013

Don't Eat the Buttercups

A weekend hike with our friends Steve and Amy* was educational as always.  There was a wide variety of newly emerged spring wildflowers to identify as well as the old standbys like the ubiquitous buttercups.  Amy just sent me some followup information on buttercups, including why not to add them to your salad.

Buttercups are in the Ranunculus genus, with over 600 species worldwide.  They vary from our typical yellow ones to pure white with a yellow center.  While many can have distinctive features, the species underfoot here requires closer inspection to pin down the exact name.

In addition to the bright yellow petals, buttercups have a distinctive shine of melted butter on the petals.  This is seen only when the flower, light, and your eye or camera are at the perfect angle.  This distinctive shine of all buttercup species is is due to specialized cells spread below the petals' surface cells.  Pictures from this website will demonstrate the difference a viewing angle can make in the shine.

Buttercups contain a irritant juice, bitter in taste which causes pain and inflamation.  "Beggars in the middle ages rubbed the leaves of buttercups on their arms and legs to produce blisters and ulcers in order to look more pitiful and thus collect more money."**  Native Americans would crush the root to treat skin wounds.  Now days we consider the plant to be poisonous when eaten.

According to Ecokids, "The buttercup gets its name from an old English game where children hold a buttercup flower under each other's chins.  If it leaves a yellow mark, then the child likes butter. The yellow mark is actually pollen."  Interesting but not likely to displace the video games on the cell phones of our current generation.

Speaking of pollen, there is lots of it in the air and plants right now.  Hayfever and swollen eyes are starting the last few weeks.  This microscopy-uk.org. website mentioned above has good closeup pictures of buttercup's pollen production.

*   Amy D. Short and Steve Craig, The Fishin' Magicians
** Ozark Wildflowers, Don Kurz



Monday, April 22, 2013

Spring Butterflies

One of the most welcome signs that spring has arrived is the sighting of tiny butterflies.  We are now seeing a lot of small white butterflies fluttering close to the ground.  The one above on my thumb tip (no, that is not my bald head!) is an falcate orangetip male, Anthocharis midea.  The females are all white on top, lacking the orange tip. (more pictures here)

Spring azure- Wikimedia
The first emerging butterflies in flight are usually the spring azures, Celastrina ladon.  These tiny blue butterflies flutter along inches off the ground in search of the very few nectar sources available.  They look like a "bald" Eastern tailed-blue, lacking the tiny hair at the end of the hind wing as well as the orange spots on the wings.


The spring azure lays its eggs early, producing caterpillars that feed on flowers and seeds as well as early leaves of plants.  This is a useful trait during the receding winter when leaves are at a premium.

Spring azure- Wikimedia
The azure's emergence is welcomed by some species of ants.  Like their cousins, the other "blues," the spring azure caterpillars produce a sweet substance on their backs called honey dew.  Some species of ants actually farm these caterpillars like tiny sweet cows, protecting them from predators in trade for licking up the honey dew.

Spring azure caterpillar- T. Murray*
Their adult lifespan is only a few days so mating takes precedence over searching for nectar.  The males will collect at puddles and wet soil, picking up the minerals to add to their sperm gift to the females.  Much of their frantic flight is patrolling for females which are settled on the low lying foliage.  More spring azure pictures here.

* Tom Murray's author of Insects of New England and New York.  His caterpillar pictures are at this PBase link.

Saturday, April 20, 2013

A Frog to Love or Hate

Coqui caught- Julia Siler- WSJ
Hawaii has an invasive species that sings way to loud.  Coqui is a tiny frog with a big voice - think a spring peeper that lives beside your house.  The frog has an enemy, Keevin Minami, the "frog whisperer."  Working for the Hawaii Department of Agriculture, he is expert in singing them out. He has perfected their call, getting them to jump into his tube trap.

Like the spring peepers that are a welcome sound of the coming of spring, (Yeah right- back to 32 degrees tonight), Coqui has its fan club.  As described in this this Wall Street Journal story, they are beloved in their native Puerto Rico.
"In Puerto Rico, where the frogs are native, the coqui is the official mascot of the island, says tourism representative Reuben Castro. He likes the frogs and describes their sound like a whistle.
The chirps of the coqui are so popular some recording artists have incorporated them into their pop songs. A saying there is "Soy de aquí como el coquí" (I'm from here like the coquí), according to a private Puerto Rico tourism website."
While most invasive species have few redeeming qualities and no defenders, coqui is an exception.  Sydney Singer, a medical anthropologist, has a passion for collecting them from the authorities and, are you ready for this?, is promoting air freighting them back to Puerto Rico.  He has created a preserve for the captured frogs and is promoting Frog Repatriation and Overseas Gifting program, or FROG.  His website is at hawaiiancoqui.org.  There is even a book he has co-authored titled "Panic in Paradise: Invasive Species Hysteria and the Hawaiian Coqui Frog War."

They sound kind of cute to us, but then we don't have to live with them.  Whether the call is pleasant or a scream depends on which island you live on.  You can listen here to decide, then consider contributing to their air fare or euthanasia.  Kind of reminds me of our Canada geese.

Thursday, April 18, 2013

Lonesome Chuck

Lonesome Chuck- Photo from Marvin De Jong
Marvin De Jong sent out this picture of "Lonesome Chuck," a male prairie chicken in a small and isolated Missouri prairie, looking for love without success.  As the patches of prairie become more isolated, the prairie chicken populations of Missouri face extirpation.

Chuck now lives on a prairie which has no hens.  Since existing prairies are separated by miles of farmland, he is unlikely to find a female, but that doesn't stop him from trying.  Greg Swick's video here of Chuck clearly emphasizes his loneliness as he calls in vain, with a response only from a distant dog and the wind.

There are other prairie chickens on a few other prairies in Missouri and some populations are holding their own for a little while but efforts to restore the former populations are challenged by the lack of contiguous prairies that are common in Kansas.

Heath Hen male- 1909
"Booming Ben" was truly the last of a breed, the heath hen, a related grouse which was quite common on the East coast during colonial times.  They were hunted down to small numbers and became extinct in 1932.  Ben was the last one alive.
"By 1927 there were only a dozen or so heath hens left.  After December 28th, 1928 there was only one heath hen, a male.  The islanders had named him “Booming Ben”.  For the next three years Ben showed up every spring to call out to any female hen that would listen.  He would eat corn in Farmer Green’s field hoping to find a mate.  He waited and waited to no avail.  On March 11, 1932, Farmer Green saw Ben scurrying under a bush.  That was the last time anyone ever saw Ben again.  He had lived a lonely solitary life booming his soothing call across the fields waiting for his true love to answer.  He died that year, alone, the last heath hen."  joanharvest.wordpress.com
Booming Ben was probably the only bird extinction where we could identify the last living victim.  Our Lonesome Chuck's problem is really more of a personal problem...for now.  His plaintive cry captures the price of fragmentation of our prairies and the subsequent loss of diversity, giving you a bird's-eye view of the possible future of the Missouri prairie chicken.  It will break your heart as well as it does his.

As with many threatened charismatic species, there is a conflict between viewing them to preserve the memory and celebrate the species versus the threat of our close presence to their safety and reproductive behavior, i.e. loving them to death.

Lonesome Chuck- Photo from Greg Swick
There is also a question whether Lonesome Chuck is calling hens in vain or simply defending the territory for reasons built into his bird brain.  It is natural to want to help even an individual bird.  When asked about the feasibility of moving Chuck to another prairie, Max Alleger, a grassland bird biologist with MDC gave this thoughtful reply.   

"Some recent history:  During the winter of 2011-2012, two wayward, radio-marked KS hens made their way from Wah-Kon'Tah Prairie to the prairie complex NW of Lockwood.  One survived the winter, mated with one of two local males and successfully hatched a brood of 14 chicks.  Several weeks later she was killed in a fence collision; we don’t know the fate of the brood members.  It is possible that the two males booming at (and near) Shelton are male siblings from that brood.  If true, they lacked access to a traditional lek occupied by mature males last fall.  They had no opportunity to, ‘learn the ropes.’  The lek is the social center of prairie-chicken life and the lessons learned thereon by juvenile birds are likely much more important to future behavior than we understand.  This poor fellow may not even realize he’s a prairie-chicken; he is driven to defend a bit of turf this time of year and, knowing no better, he takes-on all comers regardless of form.  I’ve watched chickens in several states and can confidently state that this is not the behavior of individuals on occupied leks in landscapes with healthy prairie-chicken populations.  I suspect the birds did not behave in this manner when the prairies were first settled by Europeans, by which time they had a thousand generations of collective experience with native people.

I liken the behavior being witnessed at Shelton Prairie to the death rattle of a local, profoundly isolated sub-population.  In my opinion, it should not be seen as a cool experience.  Rather, it represents a sobering reality that has likely played out many times across Missouri’s prairie landscapes over the past hundred years.  It almost always ends in the same manner – the confused male finally gets killed and prairie-chickens in that place become just a memory, a historical account.  According to Steve Clubine, “Fred” - the last male in Audrain County- was killed by a vehicle while booming in the intersection of C and D Highways.   The last male at Whiteman Air Force Base was taking on jet planes.  Residents in southern Henry County brought in photos of the last local male roosting on a school bus, challenging a tractor and flogging the landowner’s hand while booming in his driveway.  A few years ago, I heard reports from a construction crew working in rural Bates County of being approached and followed by a lone male.  Just a couple years ago I received close-up pictures of a lone male on private land in Barton County.  I’ve heard similar stories from other states as well.

We won’t attempt to move this bird from Shelton Prairie.  There is an outside chance that females remain in the landscape, or that another hen may disperse from the Wah-Kon’Tah / Taberville landscape to northwestern Dade County.  This is obviously a very slim chance.  Regardless, his proven lack of, ‘prairie-chickenness’ does not make him a great candidate for release on a functional lek elsewhere; his behavior is unlikely to change in a different landscape."

Maintaining the remaining prairies and restoring them when possible makes good sense as an investment in our future.  Trying to adopt a single bird probably doesn't, except in the case of genetic and breeding programsWe have what we call Grandma's Rule -- "Some things just need a good leaving alone."

(Thanks to Marvin, Greg, and Jeff Cantrell for their photographs and insights.)

Addendum April 29th, 2013 
Kyle Hedges of MDC reports:
"Ironically, yesterday while waiting  for the news team, I spotted a hen out in the field with him. We absolutely, positively have not had a hen around. Then, I finally got a good enough look and sure enough, she had a radio collar on. Same thing happened last year, an Eldo radio bird flew all the way down here and found him. So, we will start tracking her and see what happens."  TV news video

Monday, April 15, 2013

Predaceous Diving Beetle



We found several of these beauties while netting in the ponds for newts. Barb immediately identified them as predaceous diving beetles (PDB).  With the name predaceous, I decided they weren't to be handled.  Good decision... their "bite" injects digestive juices, like many other beetles and bugs such as the assassin bug, digesting their prey within its body before  sucking the nutrition out of them.  Having your finger partially digested is said to be a rather unpleasant experience so we slid them into containers using a no touch technique.


Cybister fimbriolatus
With a quick trip to the computer, we were able to identify these as Cybister fimbriolatus in Bugguide.  They are members of the family Dytiscidae which are all commonly called predaceous diving beetlesThey quickly scrambled over the net and are equally quick under water.  

The hind legs, which are flattened and have coarse hair-like appendages, act like paddles as it swims using a rowing technique.  They tend to hangout under water, clinging to vegetation, waiting for dinner to swim by.  They will occasionally chase their prey but usually just wait to be served.

Rowing legs- Patrick Coin
And what do they eat?  Anything they want to.  PDBs are voracious predators, consuming worms, insect larvae, tadpoles, snails and even fish bigger that the beetle itself.  There are videos of PDB consuming a hamster embryo that were too gross for this family page.

The adult has an interesting method of getting its oxygen.  Lacking gills, it swims to the surface, raises its elytra (hard wing covers) and breathes through spiracles on its abdomen.  It hangs on the surface, butt up while keeping its head below the surface to look for prey and predators.  It traps air under its elytra and then dives quickly back down where it breathes in the trapped air, staying underwater for prolonged periods. Click here for pictures of a dramatic dive.

PDB larva
C. fimbriolatus larvae are equally predaceous and aggressive, earning their name "water tigers."  Like most beetle larvae, they look totally un-beetlelike with their long slender bodies and six legs scrambling along the bottom of their pond.  Click here for some PDB larvae scrambling around to the background music of Tuvan throat singers.

Several sources say that PDBs have few predators themselves as they "taste bad."  This always makes me ask "how do we know that?"  Are there biologists who specialize in taste testing?  Do they sip, lick or nibble?  Do they rinse their mouths between each taste?  And how do we know that it tastes bad to a potential predator?  After all, a fish will gobble up a worm or a slimy leach with relish.

Life for C. fimbriolatus isn't totally a bowl of tadpoles.  An article in Pubmed describes a nematode parasitoid which infests it, just like the horsehair worms we recently describedThe worm, Drilomermis leioderma apparently only infests our beetle.  The good news is that 40% of the affected beetles survive for several days, even if several worms have emerged from it.

You may find them occasionally around your porch light.  They are capable fliers, out looking for another pond or a mate.  Are PBDs good or bad?  The answer to that question is always "it depends."  They eat fish and aren't eaten by many other creatures.  However they (a) do eat mosquitoes larvae and (b) in many cultures they are in turn eaten by humans.  I think I will pick (a).

On Bull Creek, no diving beetles were harmed or consumed.
Raising PDB as pets
Life cycle of Dytiscus (PDB) 
PDB information from MDC.

August 31, 2013
I can now attest to the reputation of the water tiger.  I reached into a net today to grab a little squirming critter and felt an intense pain in the tip of my finger.  It swelled up over a minute and continued to throb for an hour.  I think I will recognize this creature next time.

Diversity Inhibits Invasive Species

Bull Thistle
We know that diversity is important for the survival of many species which are threatened.  Now there is some evidence that plant diversity in an ecosystem can inhibit the spread of some invasive species.

A study reported at prairieecologist.com looked at the growth of bull thistle (Cirsium vulgare) and smooth brome (Bromus inermis) in 24 experimental prairie plots.  Half of the 3/4 acre squares were planted with 8 grass and 7 wildflower species.  The other half were planted with 100 species.  They found that the more diverse test plots contained less of these invading plants.

Bull thistle and other invasive thistle species are difficult to control due to the thousands of light feathery seeds the wind disperses over the field.  In many states like Kansas, the persistent presence of them in your field can lead to a daily fine.  Controlling them requires early spraying of the flat rosettes and later pulling or digging them out before they go to seed.  Anything that reduces their spread is welcome.

A separate pilot project studied these areas for the presence of poison hemlock.  Walking transects and counting the number of plants one meter on either side of the line, they came up with the rather impressive figures illustrated below.

Hemlock stands tend to be dense and choke out any other growth as they reach their 6 foot plus height.  They are poisonous to cattle (just ask Socrates) but for our purposes, they take over the landscape, eliminating other native species.

Poison hemlock stand
As I am married to a woman addicted to the removal of invasive species, I am "encouraged" to join her for a walk the fields with a sprayer (if I want dinner that night), looking for small hemlock and thistle before they get a head start on us.  The above is good news with a strong caveat.  It takes a lot of work and money to convert old fescue fields to native species.  Knowing what a typical mix of warm season grasses and forbs costs, I can only shudder to think what a field seeded with 100 species would cost.

The other obvious message is the importance of maintaining diverse species where they occur naturally.  While "nature abhors a vacuum", most invasive plants love one.

Friday, April 12, 2013

Where Are The Monarchs?

Picture by Patrick Coin
When we recently drove to Colorado, we carefully checked the weather to decide when to leave and avoid the bad kind.  It turns out that monarch butterflies' migration is weather dependent for a different reason. Their travel plans are temperature dependent and they probably don't use the Weather Channel.

Lisa Bakerink* sent this interesting link which follows the monarch spring migration.  Last spring, the warmest on record, the monarch migration was much further north by now.  Their progress is linked to the growth of milkweed.  If you are a monarch momma, you need to wait for the milkweeds to emerge before laying your eggs.  These eggs will produce the next generation which will then arrive in Missouri.

The maps below show the effect of temperature change on migration.  This year's cool spring has slowed the first appearance of many wildflowers and insects.  The ticks we have been pulling off for over a month have been the exception.  Under magnification, some seem to be wearing tiny Under Armour suits to keep warm.  (Editor's note- that is just his cataracts).


This all serves as a reminder that monarch butterflies need help.  With increasing lands being converted to agriculture, fragmentation of land and more extensive use of Roundup ready crops decreasing native "weeds" like milkweed, their numbers are way down.  Plant milkweed.

* Lisa Bakerink is president of Friends of the Garden whose Butterfly House will open on May 10th.  The Butterfly Festival will be July 20, 2013,  from 9:00am to 3:00pm.

Wednesday, April 10, 2013

Snapping Turtle

While looking for amphibian eggs, I circled a small pond by our cemetery and nearly stepped on a rounded grey rock laying in the boggy leaf-covered mud.  I had to look twice to confirm that this rock was capable of movement.  It looked like it had a coating of dried algae and only a faint turn of its head betrayed the presence of a big snapping turtle.

We watched each other for several minutes.  When I got out my camera, it raised its chin some, following me only with its eyes.  Only when it was convinced that I was there to stay did it slowly turn and amble off as seen in this video I posted on Youtube.


By the time I got back to the house and described it to Barb it had grown to 16" long, but measuring it with a stick a few days later, it came in at a little under a foot.  Snapping turtles are said to rarely bask in the sun.  This however was the first warm day after a long cold snap and there was no sign of egg laying so I suspect it was just enjoying some down time.

Salamander eggs stranded on bank
Since then I visit the pond daily and can usually see a little of its carapace buried in the leaf litter in the foot deep middle of the clear pond.  I have counted 25 spotted salamander egg masses around the edge, green with the internal algae providing oxygen to the eggs.  As the pond drained down some they were stranded in the moist mud.  I was torn between leaving them on the edge vulnerable to skunks and raccoons or tossing them back a few inches into the water even though my new friend might still feed on some of them.

I have a confession to make.  In 1996, having just bought our place on Bull Creek, I found a snapping turtle laboriously crawling across the field headed, I thought, for the creek.  I had always heard that they could wipe out all the fish in a pool and responded by taking its life.  I now know that they represent no significant danger to the fish population in the creek and still feel a little guilt over this barbarous act.

I went ahead and put the salamander eggs back into the pond several inches from shore, planning on moving them often if needed.  If the turtle gets a few, I figure I owe it one.  Snapping turtles can live for 40 years in the wild and the one I killed 17 years ago may have been its loved one. 

Aside from taking naps and enjoying the water, the snapping turtle and I share another trait - we are both totally omnivorous.  According to the MDC online field guide they eat "insects, crayfish, fish, snails, earthworms, amphibians, snakes, small mammals and birds. However, up to a third of the diet may consist of aquatic vegetation. Carrion may also be consumed."  They kill other turtles by decapitation, either as a protection of territory or an inefficient form of feeding.


Now I routinely stop to check on my new friend.  It is always buried in the leaves of the pond, minding its own business.  I can only hope it can forgive my past ignorant brutality to its family.

More detail is available at tortoisetrust.org.

Monday, April 8, 2013

Amphibian Eggs

Southern leopard frog eggs- note individual coating
Our first foray for morels on a rare sunny warm day was too early in the season, but like any foray into the woods, it had its own treasures.  In this case, we found eggs in several ponds where we hadn't seen them before.  One small 10 foot wide pond is only 10 years old and is way up in the woods 250 feet higher than the valley floor.  It collects water from the ridge top and we found the Southern leopard frog eggs above.  How they made it up here to start families remains a mystery to me.

We are new to amphibian eggs this year and sought the guidance from our more knowledgeable friends.*  If you too are new to this, here are some of the lessons learned.  The first one is to differentiate between frog and salamander eggs.  Frog eggs have a coating of jelly around each individual egg which can be seen in the picture below.  A mass of frog eggs may contain 500-2000 eggs.

Leopard frog egg mass in water- compare to maple leaf
Different frogs and toads may lay their eggs in identifiable clusters as seen at this USGS site.  Toads lay their eggs in long strings.  Newts wrap their eggs individually in leaves.
American toad eggs
The southern leopard frog eggs shown in the picture at the top of the page have black and white coloration.  As they mature, they lose the white color and the tail of the tadpoles start to develop as seen below.  Soon they will emerge and begin the arduous trip toward frogdom.  Only a few will survive to adulthood and eventual parenthood.  The rest will provide food for other creatures around the small pond.  It is probably best that way as there is no way this little pond could support 1,000 frogs. 
Leopard frog eggs- some showing early tails
Spotted salamander eggs have a thick layer of jelly covering the whole mass of eggs.  Typically there will be less than 100 eggs in the glob.  As you can see from the picture of the pond, the egg cluster appears as a single smooth blob with the eggs hard to define under water, compared to the individual frog eggs clustered in the pond picture above.

Spotted salamander eggs in water.
Spotted salamander eggs, were not unexpected as they breed in February.  Their typical home is in vernal pools (ephemeral or temporary) in hardwood forests, exactly where we found them.  They tend to live in leaf litter or burrows in the forest but make a mass migration to ponds when the spring rains hit.

Spotted salamander eggs- note all the eggs in one jelly coating
The thick clear jelly coating around the eggs protects them from drying out but inhibits oxygen absorption. This is especially important when the pond dries up, as happens to ephemeral ponds which are critical for many amphibians.  A pond that disappears every year means that no fish or even bull frogs live there, a critical source of predators.  Temporary wet pools (ephemeral) means more babies survive.

Imagine being an egg in the middle of the mass, far away from the edges where the dissolved oxygen in the water exists.  Spotted salamanders have an interesting and unique symbiotic relationship with a single celled green alga, Oophila amblystomatis.  The algae takes up carbon dioxide and nitrogen waste products from the eggs and photosynthesizes oxygen.  The eggs acquire the needed oxygen, continuing to develop into larvae while producing more carbon dioxide and the cycle continues.  The New Scientist article calls this The First Solar-powered Vertebrate.  The relationship has been known before but now there is proof that the algal cells exist inside the cells of the salamanders themselves.  The algae is thought to be contained in the salamander germ cells and thus transmitted to each new generation.

MDC has a spotted salamander video but don't expect a lot of action as this one was rather bored with the whole process.  Perhaps it had already bred and now was just waiting for next year, knowing that spotted salamanders have been known to live up to 32 years.  A lot more pictures and information is available at fcps.edu/islandcreekes. **

* Thanks to Rhonda Rimer (MDC) for identifying the eggs and Jeff Brigler (MDC State Herpetologist) for confirming the ID.  Also thanks to Brian Edmonds for the information on the green algae association.

** fcps.edu/islandcreekes/ecology/organism_menu is one of my favorite resources on ecology.  In addition to great photographs of many species of plants and animals, it has a comprehensive listing of Relationships in Nature, listing prey, predators, shelter and other ecological associations.  You will find its links scattered throughout the Resources link on the right.

Saturday, April 6, 2013

Accidental Invasive Species

Striped Beakfish- Yahoo.com
Most invasive species have arrived by human transport, either deliberate (the beautiful Japanese and bush honeysuckles, starlings, thistle, etc.) or accidental such as the earth worms and zebra mussel in ballast or shipping containers.

Now a newly arrived species has made the trip accidentally.  While not established or actually invasive, the potential points out what a small world we live in.  A Japanese fish arrived in a boat which floated across the Pacific washed out of their mainland following the tsunami.  The story is here from Yahoo.

Friday, April 5, 2013

Incredible Dragonflies

Swamp Darner- Patrick Coin
The New York Times just published a comprehensive overview of dragonflies.  The New York Times??  It turns out that odonates (dragonflies and damselflies) are the ultimate aerial predator with performance standards outclassing anything that the military and Silicon Valley engineers can produce.  Nature's Drone, Pretty and Deadly gives a vivid description of these wonders of nature.  Just a few of the many details includes:
  • Dragonflies have a 95% success rate in capturing their prey, far beyond the 25-50% frequency that lions and sharks achieve.
  • Unlike lions which feast and then take a day long nap, dragonflies eat their prey on the wing, ready to catch the next morsel.  One researcher watched a specimen consume 30 flies in a row, stopping only when the supply ran out!
  • When a covey of quail flush, most of us are challenged to focus on one to shoot at.  Not so with the dragonfly which can keep track of several prey at the same time.  
  • Some species such as the green darner form large swarms and migrate from the north to Mexico somewhat like monarchs.
  • Like the old saying about Ginger Rogers being able to do everything that Fred Astaire could do but backwards and in high heels, the dragonfly can dive at 30 mph, hover and fly backwards and even upside down!
Given all these aerial talents, it is only natural that much of the research is being done by the military.  Nature's Drone, Pretty and Deadly has a lot more detail and is worth a read.

Thanks to Patrick Coin for the use of his great pictures and to Kevin Firth for sending the story.

Wednesday, April 3, 2013

Questing Tick

Photo by MacroDave
Ever wonder how those ticks are impossible to see in nature and yet manage to "leap" onto you as you walk along?  This picture, featured in the March Missouri Conservationist will give you an idea of their technique.  The photograph grabbed me just like the tick would have grabbed the photographer, MacroDave, given the chance.  This particular one was a dog tick but they don't respect any species.

Ticks don't jump, fly or even chase us.  They just hang on the edge of a leaf with their six hind legs (remember that they are arachnids with eight legs like spiders and scorpions), reaching out with their two front legs looking for a little love to hug.  RadioLab says "Ticks literally stand there and wait for you (or a nice warm deer, or a dog, or one of those little ice cream trucks full of blood called a “mouse”) to come to them."

Their positioning isn't totally random.  They sense the carbon dioxide that mammals exhale and set up near the source.  Researchers describe putting out a block of dry ice on a white sheet and returning hours later to find lots of ticks surrounding it, waving their arms to this cold deity.

You can see a video of a questing tick at this site.  A very entertaining and scientific discussion on questing is found at this RadioLab link.  At the end, don't miss the Brad Paisley song about the romance of tick hunting.

Special thanks to MacroDave and the other amateur photographers like him whose special skills grace our blog from time to time.
Information of tick ID and which stages carry disease is on this PDF.

Monday, April 1, 2013

Short Wings Save Lives

Nesting Under A Bridge
Cliff swallows have had a hard time adjusting to the human invasion of the Western Hemisphere, but they are now figuring it out.  First it was the house sparrows that we brought from Europe, a species which found the swallows' nests a perfect answer to their housing shortage.  The swallows build their nests out of mud and straw, creating colonies occasionally reaching over a hundred nests.  They tend to return to the site the next year, only to find an occupied sign with sparrow handwriting.

Cliff swallows, Petrochelidon pyrrhonota, have adapted to humans by adopting our structures, building their nests on building ledges, barns, houses and increasingly on bridges and overpasses.  These have surfaces off the ground with a ledge for their nest foundation.  They feed mainly on flying insects and need nearby open fields for their aerial insect hunting.  Swallows have long  pointed wings to sustain them swooping gliding flight as they nail their prey in midair.

These swallows are learning to cope with one of the hazards of modern living - automobile accidents.  A dedicated 30 year study of cliff swallows in Nebraska by Charles and Mary Brown showed that while there are more nests on the overpasses, the mortality rate from being hit by cars is dropping.  And it may be more than learning about traffic safety.


When they studied the birds, they discovered that the roadkilled swallows had longer wings than their surviving neighbors.  In fact, they found that the cliff swallows of Nebraska have had a gradual decrease in the length of their wings over the last 30 years.  They postulate that this population may be evolving to meet the challenge of traffic.

Shorter wingspans mean that they are more maneuverable and able to take off vertically to escape the traffic.  Increased survival may provide more reproductive success for the shorter winged swallows, therefore passing along their individual genetic trait.

Whether this is beneficial in the long run remains to be seen.  When autumn comes, they still have to gather up in flocks to make the long migration to Central and South America, a trip that would probably be easier if they had the longer wings.  We will check back on this story in another 30 years to find the answer.

I ran this story by Charley Burwick, my resident bird guru and got this response:

"There is a really cool Cliff Swallow colony under the Hwy 65 south bridge over James River near the National Cemetery.  I study it each year to see if a Cave Swallow might show up in the state.  It is supposed to happen one of these days as the Cave Swallow reports keep moving closer and closer to Missouri.  The Cave Swallows will mix in with the Cliff Swallows." 

Note: Cave swallows are medium-sized, squarish tailed swallows in Mexico with some breeding colonies in New Mexico and Texas.  They belong to the same genus as the more familiar and widespread Cliff Swallow of North America. Their coloration differs subtly from cliff swallows.  With warmer climates moving gradually northward, followed by armadillo and other southern species taking up residence, can the cave swallows be far behind?