Saturday, August 23, 2014

Birds of Paradise (Caesalpinia spp)

Two pretty Birds: Selasphorus rufus visiting Caesalpinia pulcherrima
 When we bought our property in Picture Rocks in 2002, there was a run-down flower garden close to the house. We expelled half dead rose bushes and rabbit-fenced ice-plants right away. Most of our new landscaping plants were cacti and other succulents, but we also wanted a few flowers close to the house.

Red Birds of Paradise Caesalpinia pulcherrima
 At gas stations and along street medians, we saw very healthy, lush Red Birds of Paradise Caesalpinia pulcherrima. Our sandy soil and maybe our stingy watering produced much smaller plants with fewer flowers, but the main problem proved to be low winter temperatures. Coming from more tropical regions, maybe the West Indies, the plants freeze down to the ground and have to start over after a normal Tucson winter. Our bushes are still hanging on ...

Desert Bird of Paradise, Yellow Bird of Paradise (Caesalpinia gilliesii)
 We soon found another plant in the same genus, Yellow Bird of Paradise (Caesalpinia gilliesii) , that fits our climate better. It is native to Argentina and Uruguay, but has now naturalized in portions of the Chihuahuan and Sonoran Deserts. It's fast growing even under very arid conditions, deciduous and hardy to 20 degrees Fahrenheit. The branches are woody and the plant can be trimmed into tree shape. We also found that taller stems break like glass in our strong wind. The Yellow Bird of Paradise can be easily propagated from seeds. I have seen it on the southern slopes of some of our sky-island mountains and also in the wild in So Cal north around Dulzura in San Diego Co.

Anyway, the plants are not very long lived. Recently, half of a 12 year old tree dried up. When I was cutting it up, I noticed the exit holes of beetles. There might have been both Buprestides and Cerambycids it seemed. Although it seems a lot like closing the barn door after the horse has escaped, we cut up the branches to place them in a closed container. If there are still beetles hatching, we will see them.
 I am interested to see what species can feed on an introduced tree. The leguminous Birds maybe related closely enough to mesquite and palo verde to host the same insects.  There is of course no way of telling whether the beetles that left the holes had anything to do with the demise of the branch. Many species are strongly drawn to fresh-dead wood, which is still nutritious without being defended by tree sap. If I find anything, I'll add it here.

September 1, 2014 two buprestids have emerged. A small black white and red Acmaeodera gibbula and a larger Chrysobothris sp. Robert Velten from So Cal says: "Chrysobothris merkelii is a good bet, quite polyphagous. They kill senescent Albizia trees in landscaping here. Seems like most of the woody pea family shrubs and trees locally can serve as hosts."

Wednesday, August 20, 2014

Infestation 2014

The swarm settled for a photo shoot
Don't worry - I'm not going to write about insect pests and pesticides. Every year in August Pat Sullivan and Lisa Lee open their home in Ramsey Canyon to a swarm of  bug enthusiasts and herpers. Since the guests travel from all over the country and often from overseas this Infestation becomes a long out-drawn extravaganza. We feast on pot-luck, talk bugs over the gurgling of the creek, explore garden and surrounding juniper/oak forest, and visit permanent black lights.

Monsoon showers were hitting hard last Saturday and the evening temperatures fell well below the beetle-flying threshold. So big sphinx moths that can produce their own operating-heat dominated the lights.

Chrysina gloriosa
 I was on a Chrysina quest for a friend so I stayed up nearly all night, stepping over people in sleeping bags on every flat surface.... Towards the morning hours it warmed up and I actually got a few more beetles. Only a couple of hours later a scrumptious breakfast got us ready for another day of exploration.

Barabara and Warren with the new book (Photo Art Evans)
Art Evans had just published his new book 'Beetles of the Eastern US' and is now traveling the West shooting photos for its western sequel. The eastern beetles are great, and his writing superb, but this time the sequel will definitely be better than the original, because ...

Art Evans working on his new book 'The Beetles of Western North America'
 ... the bugs out here are so much more interesting! I got together with Art and his friend Paul Bedell before and after the party, helping to find some of our small hidden jewels.

Paul photographed Art and me in black and white - doesn't that look elegant!
 We explored the flanks of the Huachuca Mountains from Copper Canyon to Parker Canyon Lake and returned in the rain via Sonoita. On Sunday we had another go at Copper and Bear Canyon because the area had been so promising before the rain hit.

On roadside flowers Jewel Beetles (Metallic Wood-boring Beetles, Buprestidae) were well represented, especially in the genera Acmaeodera and Agrilus.

Over the years, my eyes had been schooled by weevil expert Charlie O'Brien. So I found many beetles in that family (not to mention that there are more weevils than any other kind of beetle).

At the party I had the great opportunity to chat about weevils with Bob Anderson, Research Scientist at Canadian Museum of Nature, Ottawa, and a very helpful weevil identifier at BugGuide.

Longhorn beetles (Cerambycidae) come in a multitude of sizes because their specific host plants range from big old Ponderosa Pines to thin grasses. Their colors can be quite cryptic when they are sitting on the bark or twigs of their host trees. Others let their larvae grow up in milkweed stems where they sequester the plants poison in their own tissues, and the adult beetles strut proudly their aposematic warning colors.

Blister beetles (Meloidae) were also very active. The gravid females of several species of Epicauta were chewing away on Datura leaves and flowers. Their larvae are predators of grasshopper eggs, and in August there is no shortage of those.

The prettiest were of course Rainbow and Panther-spotted Grasshoppers. I'm not sure whether the eggs of species are the targets of blister beetles - the very colorful parents (aposematic?) may be able to supply their offspring with a healthy dose of sequestered toxins.

It is not too difficult to find specific Leaf beetles (Chrysomelidae) if one knows where the host plants grow. Of course we did not get every species that I expected. For Red and Blue Potato Beetles and all those interesting Hispines Art will have to come back another time.

Photos by Warren Savary, Art Evans and me
Meanwhile at the party, humans demonstrated that they can be quite fascinating as well. Artists showed their portfolios and performed music, foragers brought back supplies, cooks worked their magic, Photographers tackled insects and each other, and many interesting discussions about bugs and other topics could be joined at every corner.

Here are some more of Art Evan's photos that he posted on Facebook:

Thank you Pat and Lisa for another great Infestation Party!

Sunday, August 10, 2014

A change in public perception: Killer Bees or threatened pollinators

Wikipedia says it quite correctly: "A new honey bee colony is formed when the queen bee leaves the colony with a large group of worker bees, a process called swarming. In the prime swarm, about 60% of the worker bees leave the original hive location with the old queen. This swarm can contain thousands to tens of thousands of bees. Swarming is mainly a spring phenomenon, usually within a two- or three-week period depending on the locale, but occasional swarms can happen throughout the producing season."

So 'Italian' Honey Bees are supposed to do this in spring, and not too often. But our Arizonan Africanized colonies seem to  break up more frequently, and you see small swarms at all times of the year. Big colonies are important for effective communal thermoregulation in winter. The Italian bees, supported by their keepers, usually survive very low temperatures by shivering and huddling. The African Bees are not that cold tolerant - so the cold winters in Germany and the northern US  kill them off, but in Arizona they often survive, even in feral hives. By now all feral hives in Arizona are assumed to be Africanized.
Accordingly, here in Picture Rocks  our feral bee populations were greatly reduced after the very cold winter of 2012/13. In spring of 2013, we saw very few honey bees at hummingbird feeders and bird baths (we don't have any closeby bee keepers). But all through  2014 I again saw swarms searching for homes, Saguaro holes turned into bee hives, and bees visiting  hummingbird feeders. The (probably Africanized)  honey bee population of Picture Rocks Arizona is bouncing back just fine.
Local endemic bees beware, they are going to be strong competition again.

Feral honey bees drinking at a bird bath. The whole rim was covered like this. Bees are not aggressive in this situation, or when they nectar on flowers
 In the past, swarming bees alarmed the public. Africanized Bees were seen as a deadly menace. With some justification. If those bees try to defend their hive, be careful. By hive I mean an established colony that has honeycombs and, most importantly, eggs and larvae to defend. They may attack if you get close and or do disturbing things ... like hammering or mowing lawns.
This saguaro hole on our property house bees for years. That high up they felt safe and never caused any trouble
 If you run they will follow, but not very far. A few stings are what you will suffer before you have outrun them. But deaths have occurred when people stood their ground and swatted at them or were unable to get away. The sad case of a rock climber who died hanging in his harness speaks for itself.

Resting swarm. Not dangerous at all
 But when swarms are encountered out in the open before they find a new home and become territorial, there is no threat to the observer. The queen lands on a branch, all others follow, held together by her pleasant smell. A big obvious cluster of bees hangs in a tree. Scouts will be sent out, looking for a nice hole that might be the new homestead. You can only hope that they do not chose the rafters of your house.  But the big, scary clump of bees in the tree is harmless. The stomachs of these travelers are full of provisions for the journey, and they are lazy and docile, Africanized or not. No need to run from a swarm like that. The worst that can happen: the queen lands in your beard. Then you may end up covered in bees. But not stung.

Over the last years, the mass media has been talking about the demise of pollinators and, in that context, hyped up the buzz-word 'beehive collapse'. To the ecologist these are two different phenomena. Endemic pollinator populations are definitely suffering all over the world. Important roles are played by drought and climate change, intensified agriculture, monocultures, pesticides, weed control along roads and between fields that eliminates the bees' food and kill them directly.  Equally detrimental: development, and even overly groomed gardens where mulch and plastic foil cover breeding grounds, and dead wood and plant material needed for breeding are cleaned away. It makes reproduction impossible and no pretty 'bee hotels' can make up for the loss of natural breeding places.

As for the honey bee hive collapse, it is a number of factors acting together. Mites and neonicotines certainly play their roles. So does insufficient winter food, after too much honey is removed and replaced with poor substitutes. But industrialized beekeeping and agriculture pose a problem that is more difficult to pin down. Millions of bees are shipped all over the continent, shuttling constantly between almond orchards in California, rape fields (Canola) in the north, and wherever else big monocultures demand pollinators in unnatural numbers. Thus infectious germs are distributed in a modern, borderless fashion.

This container truck full of bee hives overturned. But even save travel means stress for bees, who rely on a sophisticated orientation system that is almost certainly confused whenever they are shipped long distances
 Stress weakens immune systems, not just in humans. Researchers in Norway, for example, have clearly demonstrated the negative impact of transport stress on the survival rates of smalt (young salmon) that were shipped from breeding facilities to aquaculture farms. Those smalts

As press releases about the sad fate of pollinators are reaching the public,  the trend here in AZ has slowly changed from concern about dangerous killer bees to concerns about the well being of our Honey Bees. Again, as a biologist I'd say that the imported honey bees and the invasive feral bees (same thing but escaped from the care of the bee keepers) are by far not as important as our less visible endemic bees. But any kind of public concern about the well-being of mere insects should probably be applauded.

Lately I have seen a number of Facebook entries that described honey bees that were inexplicably dying. The presumed culprits ranged from poisonous nectar of blooming Tamarisk (invasive and bad in many ways, but not killing honey bees who actually originated in the same area as the tamarisk), to  neighbors spraying insecticides to Carpenter Bees attacking the hive, killing the inhabitants and stealing the honey..

Photo by Les Stewart, with permission
The last assumption reminded me of a famous Germa children story (Die Biene Maja by Waldemar Bonsels) describing a raid of  Hornets  (Vespa crabro) on a bee hive - they catch the honey bees, masticate them into food for young hornets, and they steal the honey. This terrible story kept me awake at night, but it is credible. Wasps and hornets are predators, and stored honey and pollen does get stolen, not only by marauding wasps but by other bees, beetles, birds, bears and men.

But Carpenter Bees killing large numbers of honey bees during a raid on a hive?  The above picture came with the story: the assumed culprit, a very large bee, impaled on a huge pin. The photographer had observed  big bees approaching the hive, a tussle, and later dead bees on the ground. He collected the evidence and came to his conclusion, probably because  Eastern Carpenter Bees  look not unlike big honey bees.

To me, the photo tells a different story: On the pin is a dead male honey bee, a drone.
While most of the inhabitants of a bee hive are females and sisters, all daughters of the mother queen, at certain times a number of males hatch from the brood cells. They have only one purpose: they will mate with new queen bees that are also emerging at that time. Young queens and drones go one bridal flights to mate, and the new queens will store sperm from this one mating to produce hundreds of offspring. So the role of the males is over after that one romantic adventure. Since they have nothing else to contribute to the well-being of the hive, the workers will not feed them. They will actually not let them back into the hive. Scuffles may happen when the gate keeper bees refuse entrance to the returning drones. Observers may think an attack is going on. No. It's just the expulsion of the useless drones. But dead bees can be found at that time. At the hive entrance, but also under a tamarisk tree close by. Look into their eyes. Those are the expired drones.

Here is a close-up of the swarm above. You can see the huge drone on the right. His eyes are big and touch on top of his head: he will be able to not just smell his beloved but see her in his aerial pursuit. Check out the smaller worker bee on the left with widely spaced eyes.


Wednesday, August 6, 2014

Low-tech beetle photography with great results

Over the last 6 years I have photographed literally thousands of Arizona beetle species with the goal of building an inventory for a field guide ...a locally specialized book for which it is very difficult to find a publisher (suggestions welcome). I still believe that photos of living beetles on a white background are the best choice for a field guide because they show the true colors, natural posture, and details more clearly than shots with more natural backgrounds.

I am working with a pretty minimal setup, so I can shoot in the field or in someone's crowded bug room. I use the built-in flash of my Olympus E-500 SLR. I orient it to hit the head of the beetle and use a small LED flashlight to brighten the hind end where the flash doesn't reach.

 I place the beetle in a rounded, smooth, white ceramic bowl. The smooth surface keeps many beetles from getting too much traction, so they stay in place. More important, the rounded walls bounce back the flash, reducing hard cast shadows to just the amount that still supports the impression of three-dimensionality. I later process the images using manual stacking and clean up the back ground.

Art Evans producing images for his new book project

With all those heavy appendages, macro photography is rarely as relaxed as in Robyn Waayer's shot from the BugGuide gathering 2013
Here is a photo of Piotr Naskrecki by Alex Wild - two absolute masters in the field, and check out Piotr's free-hand set-up!
Of course I very much admire the photos that my friends take with better cameras and elaborate multi-source flash set-ups. As many insects are quite shiny, inventive contraptions are used diffusing the flash arrays to prevent irritating reflections. And there is still the problem of cast shadows directly under the insects while maintaining enough shadow to keep the result natural-looking.

Bernard taking scarab photos after sunset
My new friend Bernard from Belgium had obviously invested in the best lenses and computer controlled flash systems. He was carrying the whole load of equipment on his trip through the western US. But he mostly impressed me with a technique that required in the end more patience and understanding of beetle behavior than costly equipment. I loved the results he (and then I, too) achieved.

Carabus auronitens, scanned from one of my old slides from the early eighties. Harsh natural lighting is one of the main problems
I have to interject here that he specializes mainly in carabids, Ground Beetles, including the charismatic Tiger Beetles. From my childhood in Germany on, I shared this appreciation for carabids, my all-time favorite being Carabus auronitens of our Westfalian oak forests. Ground Beetles, which are called Laufkäfer in German and loopkevers in Dutch, are speedy predators that can run very fast. But they also often freeze in mid-motion and sit still for minutes. They are the perfect models for Bernard's approach.

Soft indirect lighting models the textures and angles of this black Pasimachus californicus.
 He liked the cloudy sky of that morning in late July, but he also had a white umbrella ready to shade our little makeshift terrarium. Thus harsh light conditions were avoided and the beetles were much happier. They would otherwise try to hide.

A small reflector screen (foldable like windshield shades) was used to bounce in just the right amount of additional light. His hands were free to do this because his camera was on a low tripod and he remote-controlled the shutter.

Carabus taedatus drinking from a dew drop on the leaf litter. This beetle looks just drab and dark in my older photos. 
 The beetles cooperated nicely. The explored the 'natural' ground cover in the little makeshift terrarium (a flat clear cookie box)  and stopped to drink a few drops of water. They posed with their antennae held high and their legs in natural positions. Most of all, their colors and subtle textures were unaltered by flashes or diffusors.

Tiny Cylindera lemniscata
 When I got into the action, I found that my small point-and-shoot Olympus SP-800UZ might outperform my SLR with its 50 mm macro lens. This particular point-and-shoot has a super-macro setting in which the lens is extended to a fixed 55 mm, so it does not require to get as close to the subject as most other cameras with wider angles. With the typical sensor to lens relation of a point-and-shoot camera, it offers better light sensitivity and depth of field than my SLR does.

Calosoma scrutator strutting his colors
 I used no tripod or remote shutter control, but I made sure to firmly brace my hands against the rim of the terrarium.When photographing an insect on a twig, I held the twig in one hand and the camera in the other, then braced my hands firmly against each other. So any motion that could not be avoided was the same for camera AND subject. That's RELATIVELY easy (thank you, Professor Einstein!).

Super-active Enoclerus bimaculatus was not the easiest model
 I loved the results, even if there were a number of blurred shots. I avoided 'upping' the sensitivity (ISO not over 250) because higher ISO causes a lot of grain in my images (newer cameras are much better about this). I also kept the aperture rather small (never under 5.6) to keep the depth of field high. Luckily, overriding the camera's set programs is possible but not always necessary.

Atimia huachucae
 Even though I do not yet have my own reflector screen, I have been experimenting with the beetles that I collected on my last trips to Pena Blanca and Ramsey Canyon. The Clerid and the longhorn beetles were photographed in my painting studio close to a north facing window.

Oncideres quercus

Sometimes, natural light can even be too diffuse as I discovered when I posed a cactus longhorn on a prickly pear very late in the afternoon. With now shadow to ground it, it seems to float.

Coenopaeus palmeri