Sunday, September 21, 2014

Insects of Cochise County for the Master Naturalists Program

On Friday, I gave a 3 hour 'Insect' lecture for the Master Naturalists of Cochise County. Thank you Sheri Williamson and Tom Wood (Southeastern Arizona Bird Observatory) for inviting me!

 I had no idea how well informed my audience would be. Interested, I assumed, because they are naturalists. But still, where to start? Tom introduced my talk saying that I would now show them the hundreds of species of Cochise County insects. Requests to use English names instead of scientific ones came up shortly. I guess that would have been a way to stick to 'hundreds of species' instead of tens of thousands, but it would have excluded almost everything beyond house and garden pests and the pretty ones: Butterflies, Dragonflies, Tiger Beetles. Those all got English names now, and there are good illustrated field guides to identify them. But I wanted to challenge my audience to look beyond the already well-known bugs and I certainly did not want to end up following the media rut leading to Monarchs and Honey Bees. 
 So instead of introducing insect species in pretty pictures or even the spectacular rarities of Cochise County that attract seasoned insect collectors, I had organized my talk around themes.


Not all critters that we call bugs are insects (the systematic position of insects as a class of the phylum Arthropda).


Anatomy and a touch of physiology of a typical insect. Knowing body parts and their functions helps to understand the language of field guides and to recognize special adaptations of the basic plan.  



Incomplete Metamorphosis
Life cycles, including complete and incomplete metamorphosis, followed by a short discussion of the most important orders that exhibit these traits in their development - illustrated by many examples of Cochise county insects.

Most Holometabolous Orders of Insects in Cochise County
A mimicry complex around the powerful stinger Polistes comanchus, one of our social paper wasps, is encountered among those examples.


Switching from the specifics of insect biology to their interaction with the environment:
Reasons for the extreme insect diversity of Cochise County, from the turbulent geological conditions, the location at the interface of Sonoran and Chihuahuan Desert, to the climate situation  (5 seasons) with tropical influences.

Grasshoppers representing the grasslands


Scarabs and silk moths of the sky islands

Riparian insects from the San Pedro River corridor

Tiger beetles from the dunes around the Willcox Playa
The resulting habitats of grasslands, sky islands, riparian corridor, sand dunes and salt flats are introduced with help of character species of insects and their special adaptations.

The ecological importance of insects as the bridge between primary producers (plants) and the rest of the food chain. The importance of insects as macro-decomposers in the ecological cycle.

Insect field guides - even the ones for the eastern states can be used to get to the genus, but in most cases we have different species on the west side of the Rockies. After finding the possible genus (or at least the family) in a field guide, go to the  data section of BugGuide.net (you need to be logged in for this function) to find the possible Arizona species.
 Literature and internet techniques for species identification: use your new knowledge and field guides to get close, then log into BugGuide.net, go to the group you have identified, pull up 'data' from the submenue, chose Arizona from the options under the map, then scroll down through all the identified  images until you find your species.

The talk went well. There were good questions during and after, so people were obviously following with interest. We even attracted a couple of boys from outside who snuck into the back and listened. The organizer, Tom Wood, told me that the presentation was exactly what they had been hoping for. That felt good! The only glitch was that the recording equipment wasn't turned on properly, so there is no video. Some people were truly sorry about that - they had wanted to listen to it again. I breathed a sigh of relief. Maybe this blog can help to remember the most important points.

My insect lights had been on during the talk, but the result was not too great due to the location and the mid September date. But a number of very charismatic mantids was visiting, so we had a glimpse of the excitement the light trap can provide.
       






Thursday, September 18, 2014

Between two storms and a powerpoint presentations - a visit to Annual Sunflowers

I don't have much time for insect excursions or blog writing because I am preparing a 3 h powerpoint presentation for the Master Naturalists of Cochise County on Friday, which is tomorrow. Today we were expecting Hurricane Odile to soak Arizona in deluges of rain.So I tried to be ready before possible power-outages would hit. but Odile changed southward at the last minute: no rain for Tucson.
But last Sunday I drove over to Montosa Canyon anyway. I needed some Horse Lubbers for my presentation and some Green Fig Beetles for a client.
My first stop was Amado Rd and the Santa Cruz River. A few days ago, right after Hurricane Norbert, I had seen the raging floods of that river completely fill all the space under the wide bridge of Ina Rd in Marana. On Sunday in Amado its bed was already dry again. And the Seep Willows that had been completely submersed over the weekend were now already going to seed, so I found only one single Fig Beetle.


But Annual Sunflowers Helianthus annuus were blooming. On our trips together, Eric Eaton always made sure to check what was drawn to their sap-oozing stems and leaves, often against my protest that there would be nothing but hymenopterans (wasps were what he wanted of course).


But this time there was nothing but beetles. Even the fat black bumbling things that sounded and moved very much like bees turned out to be Euphoria lateralis. Those scarabs fly with closed elytra, doing a convincing imitation of bumble bees. They were everywhere.


On the underside of flower heads and buds and also along the stems of leaves I found many specimens of three species of lady beetles. There were no aphids. The ladybugs were there for the plant juice.


 Even Fireflies like sweets - I find Pyropyga nigricans on sunflowers every year. Soft-winged flower beetles (genus Collops) were using the sunflowers as dating locale.


Sunflowers are hosts of the offspring of numerous beetle species.  I found the longhorn beetle Dectes texanus and 2 weevils that all seemed ready to oviposit on the plant. 'The right-hand weevil is Cylindrocopturus adspersus, a sunflower specialist that's an economic pest in commercial sunflower crops in the midwest. It's common in the Chiricahuas' (Henry Hespenheide). Since their larvae have to grow up within this annual plant, those three species are all very tiny, much smaller than most beetle species growing up in tree branches or even acorns.


 The leaf beetle Zygogramma exclamationes (left) lays its eggs on the tip of the plant, where the larvae will feed on the youngest, freshest leaves. I also found Zygogramma signatipennis (middle) and the tortoise beetle   Chelymorpha phytophagica  but I'm pretty sure that the latter was just visiting - it lives on a morning glory that was growing close by.


Of course, there were not really 'just' beetles. The pretty little noctuid moth Spragueia magnifica, some ants and flies and finally a flatid Ormenis saucia had joined the party.

Tuesday, September 2, 2014

The Holy Grail - charismatic megafauna - Dynastes granti in Arizona!

If all gas stations were this clean, I'd have more fun collecting Dynastes granti
The Hercules Beetles are flying! Even though some 'real' entomologists scoff at my appreciation of these big, shiny, horned giants, I am looking forward to their late-monsoon appearance every summer. One of the serious entomologists contributed the blog title, by the way. Do I smell sarcasm?


Apparently I am in good company with my appreciation for Dynastes granti. Here Ben Warner documented Bill Warner's August 13th, 2014 encounter with a big guy. Bill is one of our leading scarab specialists, but obviously still impressionable. " My theory of Dynastes being a "degree day" bug is again confirmed--they are out weeks earlier this year (with a warm winter) than last year when we had a long, cool spring."

On my Beetle Safaris with clients, I usually look for Dynastes granti at  artificial light sources with a strong UV component, like those overhead mercury vapor lights of some gas stations along the Mogollon Rim in central Arizona. The further away from civilization and other lights the better. Most of these locations are well known and draw beetle collectors from all over. Even though the competition is usually good-natured and one is at least rarely alone, it is not always pleasant to spend the night at a gas station in the middle of nowhere. But if the weather is right, a warm night after a storm is ideal, the beetle hunt in those locations is usually rather successful.

Young Ash Trees in a canyon close to Prescott
By far more interesting and esthetically pleasing are the natural gathering places of the big beetles:.   lush stands of ash trees along creeks in little canyons. The beetles love the sap of ash trees that is raising after the monsoon rains in August. To get this treat, male beetles chew through the outer bark into the cambium layer so the sweet sap begins to ooze. They pick young branches of less than 3 inch diameter that are still tender and green. The chew marks have a characteristic shape. Even years later when they are covered by scar tissue they are still easily recognizable. In fact, those left-over scars were all I could find at first. I also discovered that under some ash trees, someone had turned over the soil. Left over beetle wings told the story: Scarabs, not all of them Dynastes, had been attracted by the oozing sap at night and then burrowed into the soil in the morning. Some large mammals like javelinas or skunks had learned to search for snacks in this promising locations.   

Left and middle: fresh bark scrapings, right: old scar all on the same Ash tree
The scarab-tribe of Dynastini is mainly night active. Most species are big and muscular enough to shiver efficiently and warm up to operating temperature even when it's cool outside, and once warm, they are strong fliers. So at night they fly to their ash trees, prepare their sap licking sites, congregate and find mating partners.The males use their horns to grab rivals and toss them off the tree. I assume the winner gets the girl...but I have seen males push females off the food, too, so fermenting tree  juice may be even better than sex. Here is a report about a study investigating the evolution of the horns in relation to the fighting styles of several species of related Rhinoceros Beetles.


  I started my search in the early morning because I had been told that the beetles, once they had chewed a sap producing wound into the tree, would hang around during the day, mainly resting in place from their nightly activities. It was at first difficult to spot them because they were all rather high above my head, at about 12 feet. So I was staring up against the sky while at the same time trying to keep my footing on slippery rocks and not to stumble into the creek. Catching them was a whole other problem. The two first ones I spotted took off, buzzing like helicopters, as soon as  my net came close to their branch. In the act of mating, they were obviously alert and warm enough for immediate take-off.  They disappeared high into the blue sky. Night-active scarabs? 


 Something else moved. Disappeared behind the branch. So I scrambled across the creek to check the other side. The right size and color, but - a cicada.


Slowly a search image formed: the beetles are round and shiny like ripe chestnuts, just not brown but greenish like the ash leaves themselves. And unlike chestnuts, they were not going to eventually fall down. I had to make them. So I got a thin stick, long enough to reach the beetles while I was standing on a tall boulder in the creek. I found that single males could be encouraged to walk down from their perches by pushing the end of the stick between their two horns. By backing off, they may have reacted as they would when faced with a powerful wrestling partner of their own kind. So I coaxed several males within range. A single female fell into the creek and I fished her out.
Overall the technique was extremely exhausting but fun.


The result of an over 400 mile round trip, still cold from traveling in a cooler
During the following night I collected a few more beetles at a gas station so I went home with an even number of males and females.

video
 Dynastes love bananas. The males even do a little fighting over them. The females are all buried in the peat moss.


The beetles will augment my own breeding stock, and a few are going to other breeders. A Montessori teacher is building a school project around a pair, the insect photographer Alex Surcica ordered some as models, others will go to entomology classes, an insect festival and a museum exhibit. With some luck, they can outlive their wild brethren by any number of months.
It turns out that I did not get quite enough specimens this year.

Eggs and larva of Dynastes granti, pupa of Strategus sp. ( Strategus is another Dynastini, I have no Dynastes pupae yet)
But that's okay. Last year I kept eight females who produced eggs from September until the end of November. The eggs then rested until January when most of them turned into little c-shaped larvae. They began feasting on fermented hard-wood mulch (my own month-long preparation) and grew quickly into very substantial grubs. They are still eating and growing now, a year after the eggs were laid. For Dynastes granti, the cycle from egg, to larvae (3 instars), to pupae, and finally adult beetles can take up to 4 years. At the Arizona Sonoran Desert Museum a batch took only 1 year, but the resulting beetles were tiny and unsatisfying.


My largest wild-caught pair this year
  According to anecdotal evidence, temperatures and the availability of protein in the larval food have an impact on the length of the development time and the size of the adult specimens. But how those factors are correlated is impossible to tell without rigorously controlled experiments.

A male Dynastes granti has 2 horns. One on his forehead, one on the pronotum. By moving his head up and down, he can use the horns like the jaws of a pair of pliers. He can grab another beetle around it's 'waist' and toss him over his shoulder

And I'm really just breeding beetles for fun ... but I can already see that I could be easily tempted to add a couple more species to my beetle breeding room - there is still space on the shelfs....

Cottonwood Stag Beetle, Lucanus mazana, with egg and young larva
By the way, I just discovered that a Lucanus mazana female (our only Arizona stag beetle) laid eggs in her container and the first larvae are hatching ...

About the first photo: it's photoshopped. I was inspired by a flickr picture of a big dung beetle from Africa taken with ultra wide-angle at night in front of a gas station. So I planned on following that idea. But the situation at the Arizona gas station was so frustrating (see above) that I completely forgot about it that night. So I decided to reconstruct the scene in a photo editing program. The photo shows  very much what you'd see lying on your belly at the gas station in a mix of cigarette buds and tire-rub-off/oil slime. Except that some one would have quickly stolen the bug from in front of your lens.

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!