Detective Work

When I was a kid, I watched a lot of reruns of old TV detective shows. Some of my favorites were Barnaby Jones, Quincy M.E., Magnum P.I. and Columbo. During my summer breaks from school, I watched countless hours of these detectives as they pieced together clues and solved mysteries. Perhaps this was early practice to become a naturalist. You see, very often, what a naturalist does is detective work; piecing together clues to solve natural history mysteries. I often get emails from people wanting me to identify plants and animals. Sometimes, they only describe what they saw and, using context clues, I offer potential solutions. When I'm lucky, they send photos and, in much the same fashion, have to occasionally use clues to determine what it is. In this installment, I will offer up the photos and we'll work together to put the puzzle together and solve this mystery.

I offer up two blobs:

The first photo is chocked full of clues... These clues will be invaluable to our success in working out this puzzle.

A second blob. This one is made up of the same material, but is in a different location. This photo also has many clues that will help us solve this mystery.

Our first clues will be time and place... These items were found in the upstate of South Carolina in the middle of an incredibly hot and humid summer.

The "blobs" are still intact, more or less. So, that lets us know they haven't been weathered or eroded very much. Let's take that into account, knowing the heat, humidity and winds haven't disbursed the objects... so, they're likely just a couple or so days old.

One of the blobs appears to be on some sort of railing. Hmmm... Looking at the railing, we can see there is definitely some water in the background. Where am I apt to find railing like that with that kind of water behind it? The railing looks a great deal like metal hand railing. The same handrails that one might find in parks and public areas along the edges of rivers and ponds. Our next clue has helped narrow our location to somewhere beside, or on, water. The other blob, found only a few feet away from the first one, is sitting on concrete. So, the objects were very close in proximity.

Can we make any sense of the shape of the overall object itself or, better yet, what is in the blob? They're sort of roundish, with the one on the concrete looking a little more oval. Well, take a close look and we can start to notice short, sharp objects and flat, thin objects within each blob. What in or around a pond could give us any clues as to what those shapes are? What do we know is in a pond? Hmmm... those short, sharp objects sure look a lot like little fish bones and those flat, thin objects resemble fish scales to me. What do you think? Nothing about the bones resembles amphibian and, while the bones could be reptile, the scales are those found on fish and not snakes. So, I'm thinking the blobs are completely made up of fish parts. what do you think?

The coloration of the blob, itself, as well as the bones and scales is bleached. While it is very true the sun can bleach bones and scales, but doing so in just a couple days is far from probable. What other natural process can bleach out organic items, such as bones and scales. The chemical processes involved in digestion certainly can... so, why don't we pursue this avenue?

So far, we have puzzle pieces of time (a couple days), location (a pond), probable items (fish bones and scales) inside recognizable shapes (round and oval), with colors (bleached white and clear) that are likely due to chemicals (digestive fluids). These pieces, when placed together, show fish that were digested and bones and scales that were then left behind. Hmmm...

What eats fish at a pond? Well, the picture can get a little mirky here; but, let's work through this part of the puzzle. We've gotten this far and, I think, once we get past this point, we'll be home free in finding out EXACTLY what we're looking at!

River Otters are often found in ponds and they absolutely eat fish. But, any evidence of scales and bones would be in scat... and there is no foul smelling, dark colored feces associated with these objects. Also, why and how would an otter defecate on safety railing? So, let's mark River Otter off of our suspect list. Furthermore, there is no "whitewashing" that occurs with feces of most species. Maybe it isn't scat?

Great Blue Herons and Green Herons are seen regularly at ponds. Could it be one of them? Do they ever perch on railing? They sure do. Let's look at their diets and see if we can narrow down our list of suspects. Do they eat fish? You better believe it! Is that the only thing they eat? Well, not at all. They both eat frogs, snakes and even mice and rats. We've already established the bones are all fish and the scales are not reptile. So, if one of these species left behind these objects, they have been eating only fish. Is it likely that two species of birds that eat a varied diet have decided to just eat fish? Probably not... Who does that leave? Well, there is another bird we haven't thought of just yet...

Belted Kingfishers eat a diet extremely high in fish. While they may occasionally take small frogs and invertebrates, they are masters of hovering over water and diving head first to catch fish. OK... we have a high probability in diet. Would they perch on the railing? Yes, they sure would. But, what about a Belted Kingfisher would leave this object behind? In talking about the River Otter, we decided it wasn't scat. What does that even leave us?

Well, like Hawks and Owls, birds that eat prey items with indigestible body parts must flush those items by regurgitating the material in the form of a "pellet". Also, like Hawks and Owls, the pellet will be a compact object with the indigestible material (whether it's fur, bones, fish scales or even insect exoskeletons). Belted Kingfishers are no exception.

After eating a couple of fish, they will digest the soft tissue of the fish, leaving just bones and scales. Attempting to pass that material all the way through their digestive tracts would be pointless (as no nutrient value can be obtained) and slightly dangerous (those bones can lodge into any number of places on the way out). But, by keeping them in the early stages of digestion, they are able to effectively compress the bones and scales into a pellet and regurgitate the pellet with little danger.

Would you look at what we just did? By taking the appearance, location and context of the mystery items in the photos, we just solved a natural history mystery, And, we proved that we are all naturalists!

Excellent work, my fellow naturalists!

(A Quinn Martin Production)

Thirty Minutes

One of the things I did while in the Carolinas on a visit was to take a look at some property a private landowner is potentially looking to purchase.  Along with a representative from a local land trust who dropped by for a visit, we set out to hit a few points of interest on the large tract of land.  After driving to the entrance, we set out hiking along a creek swollen from the previous days' rains and then over to a power line right-of-way (minus the power lines).  Our next stop would be the opposite side of the right-of-way and then to one of several ponds on the property.  We walked up and down the rolling topography, taking the time to look and listen to the story the land would tell.  

Going to a few more places that we felt would be most interesting, we noticed a couple of hours had slipped right by us.  As cool as the property was and as nice as the things we saw were, none of it was unexpected.  There was at least one more place worth seeing and we decided it was worth pushing our afternoon schedules another thirty minutes to visit.  Nature, as she often does, had a little something up her sleeve for us.

Primary flight feathers and numerous pellets left by Barn Owls (Tyto alba)

(Click to enlarge)

Rounding a corner, we saw an old, abandoned structure that piqued my curiosity.  I asked if we could take a moment to investigate and then walked into the dilapidated building.  Immediately, I knew my suspicions were right and there was a very cool bird around.  In the small amount of sunlight that streamed through the holes in the structure's walls and roof, I could see the floor was littered with molted feathers and regurgitated pellets.  There was no doubt Barn Owls had been there!

I looked up into the rafters and saw two ghost-like faces staring back at me.  Two Barn Owls were reading my every movement.  These birds had not been intruded upon before and they were not happy with my presence.  I snapped a quick photo of the floor (see above photo) and quietly excused myself from the structure as not to stress them more than I'd already done.  The people outside knew by the grin that stretched across my face that I'd seen something special.  We walked down to a beaver pond as I talked about birds of prey vomiting the undigestible parts, such as fur and bones of mice, of their prey.  With the numbers of pellets I'd seen, Barn Owls had been in that building for a while.  From the center of the pond ahead of us, there was a loud coughing sound I'd only heard a couple times before that moment.

A female River Otter (Lutra canadensis) was alarmed by our approach and was, in one vocalization, warning us to stay back and warning her two pups behind her to be cautious.  Like the abandoned structure we'd just seen, this beaver pond had not been disturbed in a while, providing wildlife with a quiet and safe place to exist.  Wishing to give them their space, up the hill and away from the otter family we hiked.  At the top of the trail, a covey of Northern Bobwhite Quail (Colinus virginiana) flushed along the edge of a Loblolly Pine (Pinus taeda) stand, giving us a good startle.  Wow!  A bird that was once common in my childhood, a covey of Bobwhites are just about a thing to celebrate nowadays.  The smile that had started a few minutes ago with the Barn Owls was growing even larger.

Common Milkweed (Asclepias syriaca) blooming trailside.

(Click to enlarge)

Getting back into the vehicle, we headed back toward the paved road, but something caught my eye.  Was that a plant that is vital to an insect whose population isn't doing well?  "Can you back up a minute for me?", I asked.  Sure enough, it was a Common Milkweed (Asclepias syriaca) in full bloom.

Just one plant caught my eye as we passed, but I noticed another blooming over here and another over there, until I realized we were standing next to a a nice patch of it.  And it was swarming with pollinators!  There were Eastern Carpenter Bees (Xylocopa virginica) and Silver-spotted Skippers (Epargyreus clarus) everywhere and they were gathering pollen and nectar at a fever pitch.  Members of the genus Asclepias are vital to Monarch Butterflies (Danaus plexippus), a butterfly whose population has been dropping at alarming rates for years now.  To see such a nice patch of Common Milkweed, many of which were well over 3 feet tall (and a few that were pushing 5 feet tall), was cause for optimism.  

Two Eastern Carpenter Bees (Xylocopa virginica) on Common Milkweed (Asclepias syriaca).

(Click to enlarge)

Patch of Common Milkweed (Asclepius syriaca). Note the many plants in various stages of blooming.

My attention was soon broken by the playful song of a Yellow-breated Chat (Icteria virens), a bird I don't get to see enough of.  As a matter of fact, in fifteen years of banding birds, I've only banded a handful of Chats.  Listening to the almost comedic variations in the song, I noticed another Chat calling.  Soon, they were joined by a third and, then, a fourth.  One popped up atop a thicket of Rhubus and I handed my binoculars to one of the people present.  "He's very yellow!", he exclaimed.  I told him they can sometimes be tough to spot and to watch it for as long as it sat up.   

Two Yellow-breasted Chats banded at Fort Jackson, 5/21/13.  It is with great fondness that I remember mist-netting and banding with Nicole Hawkins and Stanley Rikard.

(Click to enlarge)

In thirty minutes, we went from Barn Owls to Otters, from Bobwhites to Milkweed.  Now, we listened to a chorus of four Chats.  Climbing back in the vehicle, nature had one more gift.  A female Widow Skimmer dragonfly (Libellula luctuosa) lit on my knee.  She was still quite new and glistened in the sunlight.  Reaching to grab a photo, I frightened her onto a nearby blade of grass.  I was able to get one shot before leaving.  I thanked nature for the time and the gifts given to me and went on my way.  With any luck, this property will soon be protected and under a larger conservation management plan.  Time will tell, but I'm hopeful.  It's too special not to be protected...

Female Widow Skimmer dragonfly (Libellula luctuosa).

(Click to enlarge)