Archive for the 'Butterfly' Category

Monarch Watch

Thursday, January 21st, 2016

Last evening we went to a presentation by Dr. Orley R. “Chip” Taylor. The large meeting room was full of people with an interest is all pollinators but especially Monarch (Danaus plexippus) butterflies.

Dr. Taylor co-founded Monarch Watch in 1992. Among the first group of people that responded to the press release seeking volunteers were about 500 from Des Moines, Iowa. Over the years more butterflies have been tagged in Iowa than any other state. Later research showed that Iowa was the largest breeding ground for butterflies roosting in the Oyamel fir forests in southern Mexico before milkweed was eradicated from agricultural fields and along roadways. Dr. Taylor is soliciting everyone’s help to increase milkweed production so that the wintering population in Mexico will rise again.

We visited the small preserves with another Monarch researcher in 2010. Dr. William “Bill” Calvert was among the first scientists to locate the wintering grounds high in the mountains between Morelia and Mexico City. The Oyamel (Abies religiosa) or sacred fir trees are where most of the Monarchs roost from November to early March before making the several generation flights to the Upper Midwest and points east.

The Oyamel is not only essential to the only insect known to migrate long distances annually to a particular location and habitat, but is also important to the local population. The boughs are used in religious celebrations, hence its second part of its name -religiosa.

We saw trees encased in butterflies and the ground littered with those puddling for moisture and minerals and sometimes those that had not survived the long winter. We were there in early March as the butterflies were getting ready to head north to Texas and Oklahoma to parent the next generation. We saw mating and even an egg on a Tropical Milkweed leaf.

These were probing the soil for much needed water. Dr. Taylor discussed the narrow balance between enough moisture so that the butterflies could utilize their stored fat reserves to survive the 4 to 5 months in Mexico and the danger of heavy rains followed by freezing temperatures that sometimes occur in these 10-11,000 foot mountains.

Here a group was clinging to stems at a seep or little spring. Many looked like their fat stores were much reduced from the plump adults we see here in the Midwest during July and August.

In thinking about ways that Iowans could demonstrate their commitment to the preservation of Monarch butterflies and all pollinators besides planting native forbs, we learned that Iowa is one of only 5 states that does not have a state insect symbol.

In 29 states there is a state butterfly and sometimes there is a state insect and a state butterfly. The Monarch is the state insect or butterfly for these states: Texas, Alabama, West Virginia, Illinois, Minnesota, Vermont, Idaho. Idaho’s Monarchs most likely are from the West Coast population that winters along the California coast. Though several states are not large caterpillar nurseries, they felt it was important to honor this iconic and important representative of the biodiversity that supports us all.

Perhaps Iowa should do the same.


Thursday, July 30th, 2015

Yesterday afternoon the Monarch caterpillar attached itself to a heavy vein on the underside of one of the larger milkweed leaves. This was instead of using the supply of sticks we placed around the milkweed stem. The silken pad is dense and strong.

After several hours had passed it released  its three pair of front legs and seemed to still be making chewing movements with its mouth parts. The head capsule moved about. Next came the releasing of the rear pair of prolegs.

Then about every passing half hour, another pair of prolegs would release until one pair still held the caterpillar in a horizontal plane.

Finally the last set released as the video function of the camera was recording.

It was still swinging and had not yet converted to the J position when the camera was switched back to still images.

Because the underside of a Monarch caterpillar is rarely photographed, we though we should include this image. The colors were fading from the underside while the top side was still more vivid.

Here it is in the “J” position in which it can hang for as much as a day. This caterpillar stayed as a “J” from about 9 last night until a bit after noon today. The tentacles are starting to droop which is a sign that it will soon pupate. The “J” position also straightens a bit when that is close.

Since it was not yet straightened there seemed to be time to do a couple of needed tasks before making more images. When Linda got back downstairs to the tabletop setup, its skin was lying on the table and it was gyrating and compacting itself into a classic chrysalis. The skin was intact except for the split on the back. The tentacles and skin covering the feet are still discernible.

The yellow and green of the newly pupated monarch was being pushed about and shaped as it twisted itself into shape. The shiny black cremaster that will hold the chrysalis to the silken pad attached while its skin was being shed.

The chrysalis continued to become more interesting as it hardened. It is very shiny and the gold dots are still developing.  For this image, cross polarization of the flash and the lens was done to tame some of the sheen.  This image was made with a single flash rather than two which is customary.  There is more modeling with the shadow. The chrysalis is shown duller than a typical very shiny chrysalis but more of what is happening inside can be seen.

Cross polarization involves placing polarizing film in front of the flashes and using a circular polarizer on the lens. It is a way to minimize specular highlights on shiny objects.

Now we have to wait about 10-13 days to see whether the butterfly is male or female.

Monarch Caterpillar Progress

Tuesday, July 28th, 2015

This morning the Monarch caterpillar that we have been following since we found an egg on July 15th is continuing to grow. It hatched overnight on the 18th/19th. It is now 10 days old and in its 5th instar. It grew 10mm since yesterday and is 45mm long. At this rate it is likely to be a larger than typical caterpillar when it pupates.

We have joked that if we were raising a group of caterpillars we should be calculating its growth rate and EBV (estimated breeding value). Bob was an animal scientist.

The white spots on the prolegs are distinct and its colors are more vibrant.

As it is getting longer, it is able to be more acrobatic while moving around the Common Milkweed stem on which it now resides. There are also several sticks with slanting stems in the vase where we hope it will choose to pupate. In our experience they seem to like stems that slant enough to allow them to establish the J position in preparation to becoming a chrysalis.

Instar 5

Monday, July 27th, 2015

The Monarch caterpillar shed its skin one more time to become an instar 5. It was a long process. It had become lethargic on Saturday afternoon and stopped eating. Its tentacles were very drooped and limp appearing. During the night it shed its skin to become an instar 5. The shed is right behind it in the top photo in a crumpled accordion.

It was about 28 mm long at this point. Over the next several hours its head capsule darkened from yellow to stripes. Its posterior also changed from greenish yellow to striped.  In lay still most of the day. The only movement we saw was occasional twitches of its tentacles. They seemed to be inflating very slowly. We wondered if it was going to perish.

Then last evening it ate about 1/6 of a milkweed leaf and was 30 mm long. It was just lying quietly after that. During the night it chewed upon several leaves and this morning (lower photo) is 35 mm long. Its tentacles are still a bit floppy but are more filled out. The black bands are wider than earlier instars.

One of the characteristics of a 5th instar is that the front set of legs are smaller than the 2 pairs just behind them. That is apparent in the top photo.

The caterpillar may grow to 45 mm in the next several days before pupating. We hope to be present to photograph that event.

Instar 4

Saturday, July 25th, 2015

Our Monarch caterpillar was 23 mm long this morning and an Instar 4. Its front tentacles are about 5 mm long. The first pair of legs are closer to its head than in earlier instars. The lens is closer to the caterpillar in the headshot than for the entire caterpillar below. Neither file was cropped.

These two images were made from opposite sides of the leaf with the caterpillar in the same position. It remained quiet for several minutes which was helpful to the process. Adequate depth of field was difficult to maintain at this magnification and because it is getting larger and rounder.

It has been in a box with leaves. It should stay at instar 4 for several more days. When it gets to instar 5 it will be placed on a stalk of milkweed in a vase that will be surrounded by a mesh cage. The mesh cage is so it cannot wander when it is ready to pupate. One year we found a chrysalis hanging under a window sill when a caterpillar went missing before we put the cage over the vase.


Thursday, July 23rd, 2015

We just checked on the Monarch caterpillar. It is definitely showing the characteristics of the third instar. It is 13 mm long and its tentacles are growing. The black, white and yellow sections are darker and more distinct. It is velvety and much less reflective than in earlier instars.

It is interesting to note that it sometimes eats in between the larger veins like the one above it. That must be a way it controls the amount of latex it consumes.

This image was made with a 100 mm macro lens with a high quality close-up lens attached. A ring flash was used with different powers on the left and right sides so there is a soft shadow on the lower side of the caterpillar. As we said in an earlier caterpillar post we are trying a variety of lens, tele-extender and extension tube combinations. The close-up lens is another tool to consider when photographing small subjects.

We have a variety of step-up and step-down rings so the close-up lens and ring flash can be used together and/or with our lenses, other than the long telephotos.

As it gets larger we will try other combinations.

Instar 2

Tuesday, July 21st, 2015

Our Monarch caterpillar is in the second of the 5 instars that it will progress through before pupating. The time between two molts in larva is called an instar. An instar 2 caterpillar is 6 to 9 mm long and has tiny front tentacles and little knobs for back tentacles. The yellow triangle on its head with the diagonal yellow stripes are diagnostic of the second instar.

This morning the fresh leaf it was eating had a number of small, sometimes round holes adjacent to one another as seen above. Monarch caterpillars make  circular trenches around places they intend to eat. The trenches keep the latex from flowing into the area. This limits the amount of latex and toxic cardenolides that they ingest. While cadenolides provide some protection to caterpillars because it imparts a very bitter taste and toxicity to any bird that might eat a caterpillar. Too much cardenolides can also be toxic to the caterpillars.

This evening it is 8 mm long and getting quite plump. This uncropped file shows it over twice life size on the sensor because of the lens combination being used. Though the front tentacles are black, they are still translucent. The thin stripe and yellow head capsule could be seen through the top tentacle in the original file. This small reduced resolution jpg does not show this clearly.

The caterpillar has moved to its third leaf this evening. It ate a great deal of its original leaf (below) yesterday and overnight. This morning it moved to a second leaf (top photo) where it grazed and rested . When it is eating on one leaf we add a second beneath that one in the box where it currently lives. When it moves to the lower leaf we take out the chewed one and put a fresh small leaf from near the top of a milkweed plant under that.

This is the remains of the first leaf it ate yesterday. The latex sealed around the trenches and did not flow into the areas that it ate.

When it molts to the third instar, it will probably be moved to a milkweed stalk in a vase. It then can choose leaves anywhere on the plant.

Another Good Egg

Sunday, July 19th, 2015

We often check the leaves of Common Milkweed plants in the area looking for evidence that female Monarch butterflies have found them. On Wednesday after visiting the Chimney Swifts, we saw several plants along the long lane to their location. Under one leaf was a very pretty, very tiny Monarch egg. We brought the leaf home to watch and perhaps photograph the life history of another Monarch butterfly. It has been several years since we raised Monarchs from egg to release outside in our living room.

It must have been recently laid because 3 days later (the typical timespan is 3-5 days) on Saturday morning a tiny 3 mm thread was walking away from its first big meal. We know it was 3 mm after eating because we made a couple of images while holding a scale near the leaf. It was probably closer to 2 mm when it hatched during the night.

While photographing it a couple hours later, the little caterpillar suddenly swept its tail around in front of its face and deposited a fecal pellet. It just looked at it and then went on to explore the leaf to look for another good meal location.

This morning it had eaten a large hole in the leaf and the remains of digestion were scattered in a “bathroom area” a short distance from the hole.

It is now about 5 mm long and its strips are more apparent.

While attempting to make some video of its movements and eating pattern, we learned that it does not like the constant light of an LED video lamp. Even though LED light is cooler than other lights, it was agitated and crawled through the hole to the other side of the leaf.  Flash is OK with it, as it is with most creatures. Flash very rarely bothers animals.

The top three images are crops. The bottom one is the full file. Over the course of making these and other  images, we have tried various combinations of tele-extenders and extension tubes on a 180mm macro lens. For while the caterpillar is very small, we settled on the camera followed by a 2X teleconverter, a 25mm extension tube and then the 180 mm lens. This seems to maximize the magnification possible using these 3 items.

The extension tube allows the lens to focus closer to the subject than the minimum focus distance of just the lens.  In this way it magnifies the subject slightly on the sensor or film. The lens will no longer focus on distant objects when an extension tube is used. To calculate the magnification factor, the length of the extension tube is divided by the length of the lens. For example, when the 25 mm extension tube is divided by the 180 mm lens, the answer is 0.139 or rounded to 0.14. Add this to the 1X macro and the lens becomes a 1.14X lens.

The 2X tele-converter magnifies or doubles the size of the subject on the sensor or film. It doubles the 1.14 extension tube/lens combination which becomes 2.28X.

Our cameras have 1.6X cropping factors.  Multiplying 2.28 by 1.6  is 5.648 or 5.65 multiplication factor. So the caterpillar could have been enlarged 5.65 times life size on the sensor had the camera been even closer. It is not 1:1 in the image because we wanted to show the hole and the “bathroom.”

Other combinations with the 12 and 25 mm extension tubes, a 1.4X and 2X tele-converters and our 100 and 180 mm macro lenses will be tried as the caterpillar grows.

Of course, depth of field is almost non-existent with these combinations. Therefore, we use Live View to focus on the most important elements. And we need to improve our technique for image stacking. It is difficult on moving subjects.

Sparkles in the Grass

Monday, June 22nd, 2015

Every third year there is an open day at the Big Sand Dunes Nature Preserve along the Mississippi River near Muscatine, Iowa. We look forward to this field day because it is a rare habitat protected by two large companies.

This year among the lovely species we photographed was a large population of American Copper butterflies (Lycaena phlaeas americana). They flitted through the prairie and over the sand dunes like sparkly orange and black sequins. Some writers describe what we called bright orange as “bright iridescent red”. The border of the forewing is also described as dark brown. Our cameras recorded them as almost black.

With wingspans of 1 to 1.3 inches (3-3.5 cm) are sometimes spread when perched. We watched for those who were sunning in the grass. Sometimes they fold their wings above their bodies and are camouflaged by the gray speckled appearance of the hind underwings. The light seemed to come through the forewing of the one just above.

Males, in particular, are active butterflies darting from their perches in hopes that the passing insects are females. Some of them stopped long enough to compose interesting images. They may be found all summer as there are multiple hatches into the fall.

Some writers think that the American Copper may have been introduced from Europe because females lay their eggs on plants that were introduced early in settlement. The American Copper is similar to a European species. It is a bit smaller than other North American Copper species.

Whatever its origins, it is a beautiful small butterfly that provides delight in home garden or prairie expanse. It certainly was a pleasure for all those attending the field day. Now we have to wait until 2018 for the next field day on this special habitat. The preserve changes over time and those who attend are eager to see the next chapter in its story.

Snout Butterfly

Monday, August 4th, 2014

Snout Butterfly

Linda spotted the Snout Butterfly (Libytheana carinenta) tasting the guard rail along the end of a boardwalk across a pond yesterday. It was working up and down where people like to lean to watch tadpoles, dragonflies and sometimes water snakes. She had just made two images when it flew over to land on her camera. It spent the next 25 minutes exploring and sucking in the salts while exploring the nooks and crannies of her camera, lens and tripod. We have encountered butterflies who stopped for a quick sip on a camera and then moved on. This one stayed.

Snout Butterfly

Bob had the pleasure of photographing it as it did what is called ‘puddling’ on the camera equipment rather than the ground or a puddle. It did fly down to the pond surface one time, landing on some algae to take a quick drink and return to the tasty tripod. In the top image it has its proboscis in a crevice in the metal that holds an external flash. In the bottom image the proboscis is in a crevice on the screw that tightens the lens foot clamp on the tripod head.

Snout Butterfly

Snout Butterflies are also called American Snouts or Common Snouts. They are members of a small group of butterflies that are mostly sub-tropical and tropical. Their snouts are palps extending from the front of their heads.  This allows them to look like leaves on short stems when their leaf-like wings are folded to camouflage in foliage. Their wing tops are quite colorful – orange, white, black and brown. The two palps are just visible on this image.

Butterflies with pale eyes, like the Snout, appear to have dark spots that face the viewer no matter what angle it is seen. These are called pseudopupils.  Butterflies have thousands of narrow photoreceptors, each with its lens. Those photoreceptors not pointed straight at the viewer reflect light and the ones directly facing are dark because they are absorbing light. There is a good article about butterfly eyes in the Winter 2000 issue of American Butterflies magazine. Snout Butterflies were among the examples used.

This specimen was not intimidated by us. Linda turned the tripod and the tripod head, as needed, to align the wings perpendicular to the 70-200mm lens and parallel with the sensor in Bob’s camera. It just rode around as if it was on a carnival ride, continuing to suck up what it craved. It is pleasant to have willing subjects.