Coyote Hope

by Carl Strang

I don’t know the geography of those of you who read this blog. If you live in the Chicago area you probably heard something of the controversy over coyotes this winter. Coyotes are our largest resident predators (the qualifier “resident” is necessary because of the occasional wandering mountain lion). A good sized adult coyote weighs only 30 pounds or so, but they look bigger because of their long legs. Generally they stay out of sight. Here is one of Mayslake Forest Preserve’s coyotes, which I photographed from my vehicle on a recent early morning. Though they apparently spend most of their time on the preserve, I see one only once per month at best.

People notice coyotes more in winter, when they stand out against the snow and have less cover with the leaves off the bushes and trees. Even so, they generally do a good job of staying out of sight. That behavior changes, however, under certain conditions. The less capable hunters are subject to disease, usually mange, when the stresses of winter take them beyond their ability. A mangy coyote loses much of its awareness and is more likely to be seen. Another factor which can bring coyotes into the open is feeding by people. This apparently was behind the controversy in Wheaton, my county seat. A small dog was attacked by coyotes, and died from its injuries. People reported seeing coyotes in that part of Wheaton on a regular basis. The town went to the expense of hiring a trapper, who killed several animals. Nearly all of them proved to have been getting handouts.

For years, decades actually, we nature educators have been doing our best to discourage behavior that can lead to conflicts between coyotes and people. First on the list is, don’t feed them. Even unintentional feeding like leaving out extra dog food or failing to clean up after cookouts can provide meals that will bring coyotes closer. They are intelligent enough to associate people with this food source, and lose some of their shyness. The second rule is not to allow small pets to run loose, even in the yard, unsupervised. We define “small” at 15 pounds. Though clearly everyone didn’t get the message, what encouraged me about this incident was how many people were vocal in their opposition to Wheaton’s decision to remove coyotes. In my town of Warrenville, adjacent to Wheaton, a newspaper’s editorial pages criticized our neighbor city’s actions while emphasizing the responsibility of people to avoid behavior that can change the coyote’s status as an always present but seldom seen, shy consumer of wild prey. Wheaton stopped after removing 4 or 5 animals, and since has taken steps to outlaw feeding them.

This gives me hope that if we are clear and persistent in our message it will register with people, even though they may not act on it right away. For decades we nature educators have been pointing out the hazards that attend many of our civilization’s collective choices. A mistake is to categorize these educational efforts as “environmental concerns,” as if we can pretend that such behavior will affect only some “environment” over there while we can go on as usual. I think of these issues as human survival concerns. It’s clear to me that, despite all the press coverage, we don’t take them seriously. If we did, human population growth, for instance, would take a prominent place in the discussion. It seldom is mentioned. We pretend that if we just cut this emission or switch to that technology, we’ll otherwise be able to continue on as we have. The hope the coyote incident gives me is that people have heard the message even if they haven’t acted on it, and when the crunch comes they will change their behavior accordingly. The only question is, will it be too late?

House Centipede

by Carl Strang

One day last week when I turned on the shower, this little critter popped out the drain.

I rescued it from the tub, and fortunately it froze in place long enough for me to get the photo. Then it ran and hid, and I haven’t seen it since. This bug is the house centipede, a Mediterranean import I have seen in my house only a handful of times in the past 15 years.

Maybe it got in as an egg or infant on packaging. Conceivably it made its own way in from the yard. Unlike the house spiders, house centipedes are capable of living outdoors as long as conditions are humid and not too cold. I read about this after seeing the centipede, but I’m not inclined to put it out anyway should I find it again. There’s a good chance that will never happen, as they are good at staying out of sight, and it’s an interesting addition to the household ecosystem. If I see a decline in house spiders in coming weeks or months, I’ll have a suspect. House centipedes are visual hunters of insects and spiders, and are capable of climbing walls to get them.

There is an interesting internal mimicry between the antennae (right end, in the photo) and the last pair of legs. An approaching predator might be fooled when the centipede runs in the opposite direction from what the predator expects. All these interesting features are enough, for me, to compensate for the creep-me-out quality of all those long legs.

I Stand Corrected!

by Carl Strang

In a recent post I identified a shrub at Mayslake Forest Preserve as blackhaw (Viburnum prunifolium). Fortunately I have an excellent botany backstop in Scott Namestnik. In his comment he pointed to the possibility that the plant might instead be the closely related nannyberry (V. lentago), pointing to some characteristics he could see in the photo. I checked my own principal reference, Plants of the Chicago Region by Swink and Wilhelm. They emphasize two characteristics, leaf tip shape and petiole structure, that separate blackhaw from nannyberry.

Blackhaw leaf tips should be “abruptly short-acuminate,” i.e., blunt. Nannyberry leaf tips are long-acuminate, meaning that they are somewhat pinched and drawn out in a longer point, as the above photo from the shrub in question illustrates.

On the petiole, or leaf stem, nannyberry has distinct wings or flanges that are undulate, or wavy, as the photo confirms. Blackhaw petioles, if a little winged, would then be straight and not wavy.

I want to make a couple points, here. First, botanical identifications often require wading through some terminology. If you are not familiar with the terms they can be intimidating at first, but it’s simply a matter of slowing down and looking up definitions. The Swink and Wilhelm book, which I recommend for anyone serious about Chicago region botany, has an excellent glossary with drawings that make meanings clear. The only caveat is that sometimes comparisons are relative. In this example, what is the boundary between “short-acuminate” and “long-acuminate?” Here I used another tool, the Internet search. I found photos of both plants with close-ups of their leaves, and that allowed me to see the distinction.

The second point is that science works best when the scientist is egoless. This time it was easy. I had no ego invested in this identification, and I know that Scott is a topnotch field botanist. I’m a vertebrate ecologist. At the same time, however, I had the plant and all he had was a compressed photo. It was important that I go back and confirm his suspicion, both to make the correction and to learn the difference so my own botanical knowledge would be improved.

I’ll finish by pointing to Scott’s own blog, Through Handlens and Binoculars, which he and his wife Lindsay produce. It’s on the short list of blogs I follow regularly.

Catalpa Worms

by Carl Strang

Growing up, I did not have a naturalist to mentor me. There were a couple adults who knew a little, and those contacts were important inspirations. For the most part, however, I had to learn through my own time exploring outdoors, and with the limited books available at the time in Culver, Indiana (2000 people then, 2000 now). On the other hand, in the narrower pursuits of hunting and fishing I learned a lot from Dad. That was an excellent extension of my studies, but it led to some odd misunderstandings. One of those had to do with catalpa worms.

Catalpa worms I knew as summertime bait for panfish. In the loose untutored taxonomy I was building in my head, catalpa worms were, in a sense, their own phylum. I did not think about what their relatives might be. They ate leaves of catalpa trees, usually small ones, and when you found the worms they were in large numbers. You caught them, put them in a cage, took them out on the lake for bluegill, and that was as far as my thinking went.

Not until college, in fact not until graduate school, did my thoughts go back to catalpa worms. I saw them on trees at the edge of the Purdue campus, and at long last realized that they were, as should be obvious from the photo, caterpillars. Furthermore, the single long spike on the end of the abdomen led me to the sphinx moth or hummingbird moth family, as this characteristic is found on larvae of nearly all species in that family, and not in others. The catalpa sphinx moth is strictly nocturnal, a generally nondescript brown color though with the long narrow wings and heavy body characteristic of the Sphingidae.

I knew from dendrology class that catalpa belongs to a plant family that is mainly tropical. In fact catalpa is native only as far north as Kentucky. Those in northern Indiana and Illinois have been introduced. The catalpa sphinx has followed the tree to northern Indiana, but I have not seen them in northeastern Illinois. The catalpa’s exotic defensive chemistry has protected it from nearly all consumers. The catalpa sphinx’s evolution of the ability to deal with those chemicals has given it nearly exclusive access to catalpa leaves, at the cost of narrow dietary specialization.

That chemical relationship the caterpillars have turned to their further advantage by using them for their own protection. Catalpa worms are conspicuous. Their striking black, white and yellow striping contrasts sharply against the tree’s yellow-green leaves. My reading revealed that this is one of the few members of family Sphingidae that lay their eggs in clusters rather than scattered singles. The caterpillars hatch, they become distasteful to birds by consuming catalpa leaves, and birds quickly learn to leave them alone. They are not completely safe, however.

Often you encounter caterpillars like this, covered with the cocoons of a parasitic wasp. Such caterpillars have had their exoskeletons so thoroughly breached by the emerging parasites that they are doomed to dessicate.

While researching the literature on this species I remembered that some fishermen turn the caterpillars inside out when using them for bait. This was exciting, because I thought I could tie this practice to the caterpillars’ chemistry. I know of no other bait treated this way. When I consulted with Dad, however, I learned that the practice is not universal and he, in fact, did not go to the trouble.

So, while I had an amusing incongruity in my childhood thoughts about catalpa worms, it was more than compensated by the enjoyment I found later in studying them from a mature ecologist’s perspective.

Happy Familiar Things

by Carl Strang

While I have my creative side, and there’s a part of me that enjoys novelty, I also take comfort in familiar patterns. As the seasons turn, I take delight in recurring sounds and sights associated with each point in the year. Early in spring I enjoy looking for the relatively large, common bee fly Bombylius major.

I like it because of the contrast between the round fuzzy body and the long pointy beak. Mayapple leaves rise from the ground in clustered clonal colonies. Shortly after their folded umbrella leaves open, they bloom.

Spring migration brings the kaleidoscope of colors and cacophony of songs from the many birds. One of my favorites is the rose-breasted grosbeak. Here a male takes aim at an insect on a leaf.

One of the grand displays is bud break in shagbark hickories.

These spring events are all the more delightful after the long 3 seasons of winter.

Happy New Things

by Carl Strang

However familiar a landscape has become, there always is something new to discover in it. I have begun my second year at Mayslake Forest Preserve, and still I am finding rather large organisms I completely missed last year. Recently I noticed a conspicuously flowering shrub I did not see in 2009.

Unless I miss my guess, this is a blackhaw, one of the native viburnums. Fungi are an entire group with which I have only spotty, passing familiarity. Here is one of the common ones, Polyporus squamosus, which appears on the trunks of several different tree species in spring.

The scaly looking shelves of these reproductive structures are worth taking some time to enjoy. Novelty and surprise certainly are among the factors that draw me again and again into wild places, even ones with which I am reasonably familiar.

Goldfinch Song Mimicry?

by Carl Strang

In past posts on starlings and catbirds I have described well known song mimics. These are birds that include imitations of other birds’ songs in their own vocalizations. Blue jays and mockingbirds also are well known for mimicry. Sometimes, though, I think I hear mimicry in other birds. One of these is the American goldfinch.

Male goldfinches have two singing periods. Now, early in the season, they are advertising for mates. There will be a quiet time through June, then in July they will start up again to establish their nesting territories. Their songs often are distinctive, chattering jumbles with rising “zips” and “potato-chip” phrases that are unlike those of other birds. Many is the time, however, when I have heard what at first sounded like another species but proved to be a goldfinch. I don’t know if this is mimicry, or just a coincidence in phrasing and timing that momentarily sidetracks me into an erroneous identification. I think, though, that I may start a list of other birds whose songs can seem to appear in the goldfinch’s repertoire. Recently I started the list with Tennessee and Nashville warblers. Such a project can focus attention on a problem and lead to new insights.

Plants in Early Stages

by Carl Strang

Part of a naturalist’s craft is learning to identify things. We progress from entire birds to single feathers, from entire mammals to skulls and other bones. Plants have many stages, from seed to seedling to developing plant to plant in flower, each with many parts. Ideally a naturalist can identify any of these stages or parts, and have a story to tell about them. I have shared some of this learning process, most recently comparing some winter plants with the same species in bloom. One of these was the elm-leaved goldenrod. Here it is as it begins to grow in spring.

Earlier in the season I photographed some of the plants that spend the winter as rosettes, or clusters of leaves hugging the ground so as to minimize damage through exposure to the season’s stresses. Here is winter cress.

Here is the white avens.

There is wonder to experience in following the development of any living thing, and it’s well worth the effort needed to get familiar with all the elements of our local landscape. Also, there are practical applications. For instance, when an animal is eating leaves from a rosette in January, the information is useless unless one can read both the animal’s tracks and the identity of the food plant. Plus, there is always something new to learn, so the process is ever stimulating.

Happy Mother’s Day!

by Carl Strang

Recently I concluded my Winter Campfire series of posts, which discussed some implications of relativity theory. One of the great mysteries is the branching of world tubes that happens at birth. Here is a glimpse at an early cross section of my own world tube in conjunction with that of my mother, Charlene (known to all as Chuckie).

The love you see there is eternal. Now I get the opportunity to demonstrate my love in return, as Mom is going through a health challenge. If you’ve noticed some irregularity in the appearance of these blog posts in recent months, it’s because I have been needed back in Culver more than usual. We have every expectation of a positive outcome, and I have been glad to have the opportunity to spend more time with both of my wonderful parents. Happy Mother’s Day!

Bird Arrival Dates Through April

by Carl Strang

Two days ago I reviewed flowering phenology at Mayslake Forest Preserve, which demonstrated that spring is progressing about two weeks ahead of last year. Today I want to consider whether migrant birds are showing a similar pattern. There are two questions that interest me. First, is there a difference between species that winter in the tropics versus those with at least a significant presence in the southern U.S.? If weather is a factor, we might expect the closer birds to be more responsive. Second, did the U.S.-wintering species arrive earlier in March and April this year than last? Here’s one of those species, an eastern phoebe, already incubating a nest at Mayslake.

As of the end of April, not many tropical migrants had arrived. All four of those that I observed were within 6 days of their last year’s arrival date (two were earlier, two later; median 1.5 days earlier). Since they are responsive to physiological clock and day-length signals that are the same between years, this is the kind of tight pattern I would have expected.

The 27 species that wintered in the southern U.S. showed a lot more scatter, with arrival dates ranging from 40 days earlier to 21 days later. The median difference was only 2 days later, however, which leaves me thinking that these birds, as a group, likewise did not respond to the early spring. This, like the flowering phenology, I will want to follow in future years, with the elaboration of looking at the data on a species by species basis.

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