Monday, February 2, 2015

Spiders, Spiders, and More Spiders

So it's been awhile since I've lasted posted, more than a month actually. I've found myself in sort of a writing rut, and school has been a busy whirlwind of things to do so far this semester. I haven't been able to get to writing like I've wanted too. Excuses aside, I'm back.

Jumping Spider eating fly
A jumping spider (possibly Paraphidippus aurantius) chows down on a fly.
So here I am, writing a new post. This one is about a group of much feared, much hated, much maligned animals. Spiders. Why dislike spiders? I think most of that is societal. Most children are taught to dislike and fear spiders. "They're dangerous," or "They're scary." They keep that mindset as they grow up and end up passing that mindset onto their own children, perpetuating the completely-unnecessary and inane spider hate we have in our culture.

Are spiders really dangerous? A few species are dangerous. But dogs are dangerous, and horses, and most other pets. Yet people love dogs, horses, cats, and the like. We acknowledge those animals can hurt us, but we respect them in such a way that we minimize the risk of getting hurt. This is exactly how we should treat dangerous spiders, or any animal really. You don't go up and hit a stranger's dog, or any dog; that is asking to be bit. No one blames a dog that bites a person when it feels like its well-being is threatened and it must defend itself; and just like the dog, we should not hate spiders simply because we might force an individual into a predicament where that individual fears for its well-being and bites us. That is our fault, not the spider's.

Wolf Spider Schizocosa
A large, but completely harmless, wolf spider of the genus Schizocosa.
Almost all spiders are venomous, but that venom is almost always too weak to hurt a human. There are a few species of spiders with venom that can harm a human. In Ohio, we have up to three species of truly dangerous spiders. The first two are black widows, specifically the Southern Black Widow (Latrodectus mactans, photos here) and the Northern Black Widow (L. variolus, photos here). Both species are highly uncommon, but can be found throughout Ohio. They are shy, rarely encountered spiders (I've only seen one, and I've been looking for them), and a bite from them, while painful and often requiring medical attention, will almost never end in death for a healthy adult.

The last dangerous spider species is the Brown Recluse (Loxosceles reclusa, photos here), depending on who you talk to and what range maps you look at. It is unsure if we have native Brown Recluses in Ohio; ODNR says there have been no verified specimens from outdoors, but that doesn't necessarily mean they aren't there. The very few that have been recorded in Ohio have been found indoors, most likely brought in by humans from elsewhere in their range, as they like to catch rides on furniture and the likes. Regardless, Brown Recluses in Ohio are very, very rare and highly restricted to the area around Cincinnati. It is important to add a note about their bite. Brown Recluses get a bad rep for their bite, which supposedly causes necrosis around the bite area. If you're seen photos of supposed bites, you know what I'm talking about. However, studies have found that only about 37% of Brown Recluse bites actually result in necrosis (the death of tissues). On top of that, studies have also estimated that nearly 80% of all "Brown Recluse bites" have actually been misdiagnoses. Most of the time it's actually MRSA, but can also be a host of other infections. The point is, Brown Recluse bites are incredibly rare due to their shyness, and even when they do bite it will most likely be harmless. If you ever see a supposed photo of a "Brown Recluse" bite, always be wary; it's more than likely something else. Another important thing to add is that doctors are not entomologists. Unless you watch a spider biting you, you can never be sure a wound was caused by a spider. On top of that, a doctor can never positively identify a spider species from a possible bite unless they have the actual spider.

Spiders do bite, there is no denying that. And in Ohio, unless they're one of the three listed here, you will be fine. Many spiders rarely bite, and it takes a lot to make them want to bite you. You have a better chance of being stung by a bee than bit by a spider. Most spiders bite when a human accidentally begins crushing one, like if you're putting on a shoe with a spider in it, or with other cases of making the spider feel in danger. Regardless, treat all spiders with respect and obviously be aware if the spider starts acting defensively, in which case they are probably to the point of biting.

Dark Fishing Spider dolomedes tenebrosus
The spider above is one that many people completely freak out about when they see one. Meet the Dark Fishing Spider, Dolomedes tenebrosus. Dark-Fishing Spiders are some of the largest spiders in Ohio, reaching up to a total size of 4 inches across (basically the size of your palm). While massive, these guys are totally harmless. They are really shy and will many times run away upon seeing a human. Occasionally they will wander into buildings and homes, often resulting in terror-stricken inhabitants. There's no need to worry; simply try and carefully put it in a plastic container in order to release it outside! Dark Fishing Spiders are forest spiders. They do not build a web, and instead actively hunt down prey. Look for them low on tree trunks at night, or near rocky areas with water (which is where I find most of mine).

Six-Spotted Fishing Spider, Dolomedes triton
Next up we have another fishing spider, the Six-Spotted Fishing Spider, Dolomedes triton. Spiders in the genus Dolomedes are known as Fishing Spiders as most of them are at least semi-aquatic. The previous Dark Fishing Spider is not always that aquatic and can be found very far from water. The Six-Spotted Fishing Spider, on the other hand, is the most aquatic fishing spider in Ohio. These guys are really cool. This species can actually walk on water, as shown above. They will often wait on the surface of water for prey to come by, or actively hunt prey down. Water Striders are a favorite, as are terrestrial insects that fall helplessly into water, but the Six-Spotted Fishing Spider will also hunt prey in the water. They are capable of diving up to 7 inches under the water to catch aquatic invertebrates, tadpoles, and even small fish! Pretty awesome, eh?

White-Banded Crab Spider, Misumenoides formosipes
This tiny spider sitting on a flower is a White-Banded Crab Spider, Misumenoides formosipes. It's small, but note the characteristic white-band that runs across the face underneath the eyes. If you want a larger version of the photo, just click on it! This species, as the name suggests, is a species of crab spider, family Thomisidae. The crab spiders are so-named for their crab-like appearance. Most, but not all, crab spiders in the family Thomisidae are sit-and-wait ambush predators, as the White-Banded Crab Spider is. Basically, they sit on a plant like the one above and wait for an unlucky pollinator to come by. If the pollinator is the right size, the spider will lunge and grab it for a meal. The individual above is a male White-Banded Crab Spider. The males of this species have a golden abdomen with their four front legs being dark brown/black. The females of this species can range from gold to white. Interestingly, the females can actually change color to match the flower they are sitting on. For example, if a female picks a white flower to hunt from, she will become white, and if it's a yellow flower, she will become yellow. The males, like the one above, are locked in with their colors, however. Most of the time people are taught that the females change color in order to be camouflaged so they can be undetected by potential prey until it's too late. A relatively recent study (Brechbühl et all, 2006) has found that this is not the case; color-matching individuals had the same success rate as mismatched-colored individuals. The actual meaning behind changing colors is still up for debate, but it most likely isn't for better hunting success.

Pisaurina mira
And last we have one of my favorites, Pisaurina mira, also known as the Nursery Web Spider. This species loves to hang out on the edges of forests, especially when there's bushes, tall grass, and other similar herbaceous plants. I always find many at A.W. Marion State Park in Pickaway County where a medium sized marsh/grassland area transitions into an established forest. These are large spiders, with some individuals I've seen approaching 2.5 inches wide (that is including the legs). They come in a range of colors, from very light yellow-brown to a dark brown. The markings are somewhat variable as well; BugGuide has a nice layout of the different variations, which you can see here. Why are these known as the Nursery Web Spider? Like the others I went over in this post, this species does not build a web to capture prey; instead it actively hunts down prey. The females of this species (and the others in the family Pisauridae) will, however, carry around an egg sac (photo here). Upon the spiderlings nearing hatching, the female will construct a "nursery" made out of web and place the egg sac inside. After the spiderlings hatch, the female will defend this nursery in order to keep her hundreds of offspring alive.

So I ended up writing a lot more than I thought I would, but I just love spiders. I love how misunderstood they are, and they're just so amazing once you can get past the whole "ew a spider" issue so many people have. If you don't like spiders, I strongly urge you to give them a chance!

Wednesday, December 24, 2014

The Downy Woodpecker

Several days ago I bought a new 300mm telephoto lens. I've been eager to try it out, and December 21st was just the day to do so. I traveled out to a few local parks, including the newer Mary Virginia Crites-Hannan Park right outside of Circleville in Pickaway County. Although a smaller park, there's a decent patch of second-growth forest and a nice prairie they planted about four or five years ago. It's a really birdy park too, which brings me to the subject of this post. There were at least two Downy Woodpeckers in the small area I explored and I was able to get a few photos of them.

Downy Woodpecker
Downy Woodpeckers, Picoides pubescens, are probably the most common woodpecker species in the United States. They can essentially be found from coast to coast and everywhere in between, aside from some desert regions like western Texas, Arizona, and smaller parts of southern California and Nevada. They inhabit a range of forest types and even open areas where they will feed upon insects found on small herbaceous plants. Downy Woodpeckers are nearly identical to the Hairy Woodpecker, but there are a few differences to look for in the field. A big one is the size; Downy's are only about 2/3 of the size of a Hairy. Another is beak length; a Hairy Woodpecker's beak is about the same length as its head, but a Downy's beak is much smaller (as you can see above). You can read about some of the other differences here. In Ohio, when you come across a Downy/Hairy woodpecker, it's much more likely to be a Downy. Hairy's are not rare by any means though.

Downy Woodpecker Ohio

Woodpeckers are well-adapted to their bark-clinging lifestyles. If you look at the photo above, you can see a Downy's large feet with large, curved claws; this helps with clinging to bark. Woodpeckers are also a bit different from other terrestrial birds. Most terrestrial birds have feet with three toes facing forward and one toe facing backward; this arrangement is known as anisodactyl feet. Essentially all woodpeckers have zygodactyl feet, which is where two toes face forward and two face backward. This arrangement also helps woodpeckers cling to bark better. Woodpeckers also use their tail to brace themselves as they cling to bark. If you look at the previous photo, you can see this in use; the tail is pushed down against the branch in order to help stabilize the woodpecker. A woodpecker's tail is made up of very stiff feathers, and these feathers are attached to large muscles which allow for a range of fine muscle control. If you've ever seen a woodpecker climb up a tree, you've probably noticed that it climbs in short, jerky bursts instead of one fluid motion. Woodpeckers actually climb by using their feet and tail. A woodpecker will lean close to the bark, which takes pressure off the tail, and then push straight up with their legs. They will then swing their legs up quickly and grab the bark once more before bringing their tail down to stabilize everything. They will repeat this method to ascend a tree, which gives them their jerky climbing appearance.

Downy Woodpecker Ohio
While on the trail, I found another Downy on a large, dead tree. I quickly noticed it was a female Downy Woodpecker since it lacked the red found on the males' heads (which can be seen on the two previous photos). She was standing in one place and excavating a cavity. I first thought that she was excavating a nesting cavity (all woodpeckers are cavity nesters), but it seemed a little early for that. I looked around on the internet and my suspicions were confirmed; Downy Woodpeckers begin excavating their nest cavities in mid April and May. So what was this one doing?

Downy Woodpecker Excavating
It turns out that Downy Woodpeckers not only nest in cavities, but they also roost in cavities. While they mainly excavate roost cavities in the Fall, they will also do it whenever they need to. I'm assuming that this is the case for this individual. A Downy's roost cavity is built a bit differently from their nest cavity. The main difference is the depth of the cavity; a nest cavity is deeper than a simple roosting cavity. Roost cavities are also built to hold a single individual, instead of a bunch of hatchlings.

Downy Woodpecker Excavating
I stood around for awhile and watched as she worked on the cavity. Eventually she took off, probably to forage for some food.

I haven't had many bird-related posts on this blog, but that has started to change in the past month. I'm a bird-guy first and foremost, but I haven't been able to get any decent photos with the lenses that I had. With my new 300mm lens, I should have more opportunities to get some photos, and hopefully that means more bird posts, so keep on the lookout!

Monday, December 1, 2014

Black-Legged Kittiwake in Central Ohio!

I'm sorry for the short absence. I've been preparing for finals week, and then, more importantly, getting it over with. But now that finals week is finally over, I finally have a chance to breathe, relax, and blog!

During the week of Thanksgiving, Robert Royse found and reported a juvenile Black-Legged Kittiwake at Deer Creek State Park, specifically the section that lies in Fayette County. Black-Legged Kittiwakes, a species of gull, are a rare visitor to Ohio. Most of the ones that do end up in Ohio show up along Lake Erie, but occasionally you'll get one that shows up in an inland reservoir. This individual was one of those few that showed up inland. To make it even better, it showed up at a park only 30 minutes away from my hometown, and luckily I was there on break. Before returning to Ohio University on Sunday morning (Nov. 30), I ventured out in search of the then-continuing Black-Legged Kittiwake. As with many rarities, dozens of other birders had already made the trip to "chase" the bird, and dozens more would chase it on the day I went.

Deer Creek State Park
The kittiwake was said to be hanging around the upper part of Deer Creek State Park, right where Long Branch (a creek) feeds into the man-made reservoir. As I pulled over to park, the site above greeted me. You might ask where's the lake, and that's a good question. Every winter they lower the reservoir by about 14 feet. Since this part of the reservoir is where it begins, draining the lake by that much is enough to reduce the water to a small stream and leave expansive mudflats behind. The lake still remains if you head to the beach or other parts of the reservoir though.

There were already three birders present by the time I arrived there around 8:40 AM. They were scanning as I was getting my gear out, but they hadn't relocated it yet. It's always a gamble when it comes to chasing continuing rare birds, especially when you go early in the morning; it might have been there for a week straight but decided to leave the night before you went. Anxiously, I joined in and scanned the horizon, only to find a handful of Bonaparte's Gulls. Suddenly, we saw a small gull flying in from down the reservoir. Holding our breaths, we turned to the gull...

Black-Legged Kittiwake Flying
And lucky for us it was the kittiwake! I quickly tried to snap at least an identifiable photo, which is pictured above. So why are Black-Legged Kittiwakes, Rissa tridactyla, so rare in Ohio?

Range map created by Terry Sohl at South Dakota Birds and Birding. Go check out his wonderful photography!

A quick look at a range map should give you a pretty good idea as to why Black-Legged Kittiwakes are rare in Ohio. Black-Legged Kittiwakes are a true "sea gull." They nest on sea cliffs in northern Canada and all around Alaska before heading out to sea to spend the winter. Occasionally a young bird, like the one at Deer Creek, will wander inland during the winter. Adult visitors to Ohio are much, much rarer (but have still been recorded).

Black-Legged Kittiwake Ohio
After some hunting, the kittiwake decided to rest and preen on the rock above, which was its favorite roosting place (as evident from the white-wash on the rock). It really is a gorgeous gull, which are birds that many people pass by. A day or two after I visited it, it decided to head out and hasn't been relocated since. Hopefully it ventures back out to sea.

Thursday, November 27, 2014

Bird Banding

Two weekends ago on the 15th I woke up as the sun was rising, donned four layers, and made the short trek to The Ridges in the brisk 16 degree weather. Why? To go bird banding, of course! One of the Ohio University graduate students specializing in ornithology has been setting up banding stations at The Ridges, and he invited the OU Wildlife Club to see what banding is all about. Sadly, the early time and the cold weather turned most people away. In the end, only me (the secretary), Alayna (the president), Olivia Brooks (who runs the Twitter account Wild Earth), and one other member showed up.

For those of you who've never been, The Ridges is a large tract of land now owned by Ohio University which sits on the outskirts of the city of Athens in Athens County. The main point of interest is the old "insane" asylum, but there's also dozens of acres of forests and grasslands with miles of hiking trails, which I've partially covered before. The graduate student set up a total of three nets near the Nature Walk Trail in order to catch and band birds. What exactly is bird banding though? Well, bird banding is where a certified bander will place a small metal ring on the leg of a wild bird that was caught in a "mist net." Each band has a unique number and that number, along with morphological data of the bird, goes into a giant database. The idea is to be able to mark an individual, recapture it at a later date, identify the individual, and then gather more data. On a large scale, this process helps us learn more about migration routes, morphology, age, and various other information.

So what did we catch that day? I'll start off with this Tufted Titmouse, Baeolophus bicolor. This common backyard species is a part of the tit and chickadee family know as Paridae. If any of you are birders, you're probably well-acquainted with these guys. Many of the species in Paridae are known to form medium-sized flocks during the winter; right about now you'll see flocks of chickadees moving throughout areas searching for food. The Tufted Titmouse is a bit different. They actually don't form winter flocks; instead a breeding pair will continue to stay on their summer territory and search for food. Many times one of the hatchlings from the previous summer might join them, as well as other random juveniles from the area. Occasionally they will join those chickadee-based flocks. These flocks have a very hierarchical nature, and the Tufted Titmice, when they're part of those mixed winter flocks, will assume the most-dominant role.


A closer look at the feet reveals extremely long, and very sharp, talons. Tufted Titmice are denizens of forests, particularly forests with dense canopies as these provide excellent cover and foraging opportunities. A large part of a Tufted Titmouse's diet is arthropods. These large, sharp talons help them grasp the bark of trees as they search it for insects, spiders, and the like. I'm always struck by just how dinosaur-like birds' legs are; it really makes sure you're reminded of their reptilian origins.


Carolina Chickadee
Also in the family Paridae is the well-known and much loved Caroline Chickadee, Poecile carolinensis. If you know nothing about birds, you have still probably heard about the chickadee. We have two chickadee species here in Ohio. Identification between these two species is difficult due to their very, very similar appearance, but typically this isn't a problem due to the fact most people are only in one of the species' range. If you're in Athens, for example, you know 99.9% of the chickadees you'll see are Carolinas. But Ohio, as I mentioned previously, has both species. Generally, to the north is the Black-Capped Chickadee, and to the south is the Carolina Chickadee. But this also means we have a dreaded transitional zone between the species. This roughly exists along the Lima-Mansfield-Canton line across the state. What makes this line even worse for birders, but cool for scientists, is the fact these two species will even hybridize within this zone.

 
Carolina Chickadee

Carolina Chickadees are very intelligent and interesting birds. Many times this species will act as "alarms" for other songbirds in the event of a threat coming into the area. Upon sighting a threat, Carolina Chickadees will many times give a buzzy "chick-a-dee-dee-dee" call, which is where they get their name. Interestingly, studies have found that the Carolina Chickadee tailors that chick-a-dee call to the severity of each threat. For example, one study (Soard, C., and G. Ritchison. 2009) found that for lower threats (such as a Red-Tailed Hawk, which would typically not hunt chickadees), Carolina Chickadees gave a call with more of the introductory "chick" notes than the buzzy "dee" notes. On the flip-side, predators posing a significant threat resulted in the chickadees giving a call with more of the "dee" notes than the introductory "chick" notes (if there were any "chick" notes at all.) If you're interested in that study, you can download a PDF from this link.


Female Northern Cardinal


The largest bird we caught that day was this female Northern Cardinal, Cardinalis cardinalis. This bird, also called the "redbird" by some, is a very common species in Ohio. In fact, it's even the state bird (along with six other states). With most songbirds, only the male sings. Bird songs are employed by males to mark territories and to attract mates. With the Northern Cardinal, the females will also sing. While songs vary, both sexes will sing the same types of song.


Song Sparrow

The final bird we caught that morning was the ubiquitous Song Sparrow, Melospiza melodia. These are one of my favorite birds and they have one of my favorite songs. Song Sparrows don't actually have a "set" song; there's a whole range of bits and pieces that the Song Sparrow will string together to make one individual song. Many times a song will have certain parts which almost all use (like the 2 or 3 introductory notes which most songs start with), which allows birders to quickly know what they're hearing is a Song Sparrow, even though it might sound nearly completely different than any they've heard before. Song Sparrows will actually learn the songs of neighboring individuals and add them to their repertoire. An individual can know over a dozen different songs, many times with hundreds of small variations on those general songs. An individual can also improvise and tweak his songs and his learned songs to create new songs, which other neighboring individuals can learn and tweak themselves. As you can see, the Song Sparrow's use of songs is a highly complex endeavor. What's even more interesting is the effect they have on females. As I stated previously, males will use songs to attract females. Most of the times the females are attracted to the male's performance of a set species-wide song. With Song Sparrows, studies have found that females are also attracted to the male's ability to learn, which is reflected by the number of songs he knows on top of how well he actually performs them.


Bird with Tick

When the graduate student was taking measurements of the Song Sparrow, I noticed something a little odd. It looked like a tick was on the neck, and sure enough upon checking there was a blood-engorged tick attached to the neck. This tick is probably Ixodes brunneus, also called the Bird Tick. This is, as most ticks are, a bad thing. Not only do you have a blood sucking parasite, but these birds can contract a condition known as tick paralysis from these ticks. Many Ixodes tick species have a substance in their saliva which upon injection to a host will slowly paralyze that host. Eventually this can lead to death. We decided to remove the tick, so hopefully the sparrow will be fine.

That's it for this long post. It's currently Thanksgiving as I write this, and this has been the first time in a few weeks that I've had to sit down and actually write. Finals week is currently only two weeks away, so once again I'll be tossed into the college craziness when I head back to Athens this weekend. I've been slacking on posts recently and hopefully with break I can catch up. Thanks for reading!