The World is Your…Sewer??

My Lead Science Cutie on staff (who I pay with milkshakes and bizarre postcards) has given me an excellent topic. Recently I chose to donate to a group looking to limit/control the dumping of human waste into the ocean from cruise ships. Science Cutie naturally wondered how big an impact this could have on a body of water as large as the ocean. My answer was “very” and “because eutrophication”.

Eutrophication is enrichment of an aquatic environment with nutrients. It’s natural in lakes and ponds over time, I’m sure most people reading have been around some stinky, algae filled ponds in their time and will have seen what I mean (even if you didn’t all know it at the time). Besides clouding the water and filling pond and lake bottoms with sediment, thereby reducing clarity (and light available underwater), eutrophication allows algal blooms to flourish and grow. Without enough light, they’ll start consuming oxygen. During particularly intense eutrophication, this can essentially suffocate other species.

This can radically change a habitat, but natural eutrophication is VERY slow, and though the build-up of sediment and nutrients may result in the lake or pond disappearing completely, local species have been adapting along with the changing water body. I mean, the fish and stuff are toast, but the lake/pond would have been supporting less and less of those things for a WHILE. But then there’s Unnatural eutrophication…That is, human-induced eutrophication.

Now we get to the cruise ships…

Human-induced eutrophication is a result of organic pollution, as with agriculture runoff or the dumping of human waste from ships or poorly managed sewers. Dee-lightful. Besides the aforementioned depletion of oxygen and light availability, toxic algae and bacteria can effectively poison local species. In the ocean, we are most familiar with this process as Red Tide. Toxins build up in the food chain as predators eat many things with a little toxin, then something bigger eats many of those and so on. This also impacts us because, considering we have found a away to eat almost everything in the sea, our big tasty fish dinner may have consumed enough toxic smaller fish to make it toxic to US. Yay. So now we have Red Tide warnings to let us know when and where we’ve totally messed everything up. If that’s not enough, you see large die-offs as the algal blooms suffocate or poison local species, thereby significantly reducing biodiversity.

Lead Science Cutie is correct that while you may not see the full effect of ocean eutrophication on a global scale, the ocean is composed of many ecosystems supporting a WIDE variety of life on which eutrophication can have a profound impact. Furthermore, if you dump enough waste in one area (as happens when many ships cover the same routes), it will spread. Even if we took the impact on our fishing industry out of the equation, the kinds of dieoffs that result from that are BAD NEWS.

Fortunately, the effects are reversible. However, we should support high water quality standards to allow such affects to reverse where eutrophication has already occurred, and to prevent it from spreading elsewhere.

Which is why I’m going to link to the fundraiser that started all this:

Protect the ocean from raw sewage

Support if you like.

Sources

Mack, Jeremy. 2015. Lake Scientist. Water Quality. “Eutrophication” April 13, 2015 < http://www.lakescientist.com/lake-facts/water-quality/&gt;

Superb Owl Sunday

Aw damn…aw shit I MISSED IT. I was so busy with work I forgot about the most important event of the year: Superb Owl Sunday. I know I’m late to the game, but I’d like to put in the Barn Owl for Most Superb Owl.

Seriously. That is one Superb Owl.

I have heard the suggestions of osprey or guys really enthusiastic about America, but those are ridiculous ideas. Neither of those are owls. Barn owls, however! Besides being damn fine raptors, they are an excellent natural mouse trap; a family of owls will consume 1300 rats per year! How can a fish hawk or star-spangled bros compare? I don’t see either of THEM eating that many rodents.

Barn owl populations are greatly threatened by human activity and development; they’re hit by cars and they can fly into barbed fences or power lines. To help them out (besides watching for animals when driving), get an owl box! Just don’t bug them once they get settled. They don’t like that.

Sources

Frendt, Don, Andy Harmer and Phil Johnson. 2011. “Natural History”. The Hungry Owl Project. Feb 2, 2015 <http://www.hungryowl.org/education/natural_history.html&gt;

The Urban Wild Part 2

Apparently after 87 pages filled with uncommon scientific terms, Microsoft Word just gives up on spell checking. Basically I killed spell check. FUN FAKTS.

Anyway, back to Tuesday’s urban ramble.

Before continuing, I would like to clarify that I am addressing the recolonization of wildlife following human development. That is, how wildlife communities respond as human settlements urbanize (eg. develop into large towns or cities). Why is this an important clarification? Because developing land for settlement rather than for agriculture places different pressures on the local wildlife. For instance, there may be less concrete to cover potential burrow space or fewer people to scare away grazers, but farmers will discourage any potential threat to their livelihood. Farming is a tough business without Bambi’s family eating everything.

Damn adorable jerks.

Now, back to business.

Given my understanding of ecology, I can give a rough idea of how recolonization by wildlife in urban areas works. This is not perfect (you could teach a whole class on this very subject), so bear with me.

Consider urbanization of a habitat like a natural disaster; everything is changed and initially there is nothing but what humans have planted or allowed to remain (grass, trees, flowers, etc). Wild animals are exterminated or driven out to nearby wilderness, where their numbers grow to the point that some species move into human settlements just to find enough food. The order in which species move into urban areas does not follow set rules, but the order in which species successfully adapt does. Raptors, for instance, can fly in to the city all they want, but they won’t succeed unless prey animals recolonize first.

First to succeed are the small animals that can reproduce fast, these feed on/live in the surviving plants. Their size allows them to easily avoid humans (they may not have even been driven out in the first place) and their r-selected reproduction strategy (that is, they reproduce, really rell-I mean well) ensures that a few man-caused deaths do not greatly impact their population. Species that can rebound this quickly are small rodents like rats and mice (rabbits too if there’s spaces to build warrens), as well as many smaller birds that can fly away from disturbance and easily return to smaller urban trees.

Following the wee squinnies, scavengers like raccoons and crows will quickly move in, with the abundance of man-made trash and various rodents to feed on. Coyotes and foxes, being larger and slower to reproduce, do have a harder time. They stick out and come into contact with domestic animals more, so humans actively discourage their settling nearby. Even in rural areas, the presence of coyotes is met with violent opposition. However, they can and do learn to adapt.

As prey populations increase and the habitat stabilizes, predators can move in. However, urban environments severely limit the species that are able to colonize. Without large prey or any inclination to be near humans, large predators stay away from cities. As a result, the most common predators in urban areas are birds of prey. A variety of sizes, many species can coexist in a city, feeding on a variety of small birds and rodents. Besides any larger trees remaining, raptors can nest on building ledges and around support systems for bridges, overpasses and other raised structures.

That covers a general overview of wildlife recolonization. Something to keep in mind though, is that despite nature’s amazing ability to bounce back, urban environments are made to support humans, not wildlife and thus do not favor biodiversity. From the different categories I mentioned (small animals, scavengers, predators), it is a MUCH more limited number of species that will recolonize than that originally lived in a given habitat. I mean, the sheer amount of concrete in even a small city is enough to increase local temperature. Many species require some very specific conditions in order to live and reproduce.

So beyond “PEOPLE ARE BAD AND YOU SHOULD FEEL BAD”, what am I getting at? DO SOMETHING. In a broad sense, support local, national and international conservation efforts. In a more personal sense, try to make your habitat a habitat for other species; plant some trees, build a bat box, set up an owl house, etc. See what species are hurting in your area, and how you can help. Maybe start a science blog and guilt trip strangers and friends into supporting conservation!

One of the most important things is, if you have a conflict with animals, try to find an eco-friendly solution. Pests like mice and rats may be far from even hearing of the endangered species list, but plenty of raptors that depend on them aren’t. Choosing to poison household pests means you could also be poisoning local wildlife that think they’ve scored a weak and easy meal. Options like sonic repellants and snap traps can keep EVERYONE happy without impacting the rest of the food chain.

For bothersome and/or scary animals that are not an immediate threat, choose avoidance first. For instance, if you choose to attack a rattlesnake rather than back away, 1. you’re ignoring its very helpful suggestion to GO AWAY AND WE’LL ALL BE HAPPY and 2. you’re prolonging contact, which means you’re more likely to get bitten then if you’d just left it alone. Remember: people are big and scary, animals do not react kindly when scared, so just walk away.

For immediate threats, well…I’ll leave y’all to assess the situation, but generally running and screaming is a bad idea.

Resources for those interested:

Humane Rodent Solutions

Create A Certified Wildlife Habitat

Barnowlboxes.com (They sell, you guessed it! Barn owl and bat boxes and make the important point that both provide natural pest control)

The Return! / The Urban Wild Part 1

GOLLY it’s been a while hasn’t it?? So now that it’s been almost a year since I began my “little” hiatus it is high time I got back into the saddle. I’d apologize for the length of said hiatus, but I had three jobs and wasn’t sleeping well for a good chunk of it so I APOLOGIZE TO NO ONE. I’ve actually been on just two jobs for a little while, now, but only recently started thinking to myself that I needed something to suck up more of my time. No really, I sit in my room and stare at the pictures of jellyfish on the wall and wonder what to do with the free time I actually have.

I have a problem.

But my problem means fun stuff for those few interwebbers out there still interested in what I have to say! Yaaaay!…?

I’d like to pick up right where I left off, answering some questions/addressing topics brought up in my little informal Facebook survey.

“How do animals adapt to urban areas, Are humans part of the biosphere? (if so what should our role be in conservation)”

Although I can quickly and easily answer this with a resounding YES, this is an excellent question that merits a longer response. Too often humans consider themselves separate from nature; we and our cities and town are outside the “natural world” even though we built our cities right in the “natural world”. Growing up, I would have not considered going to the tidepools on the beach near my house “getting out in nature”. I could see Taco Time from there, no way that’s “nature”. Do these things somehow, in their proximity from humanity, become domestic? No, it just indicates how separate most people feel from “real” nature.

Why is this? When you think about it, there is quite a few species that have found ways to thrive around humans. Squirrels, songbirds and rodents thrive in urban environments. Omnivores like raccoons, foxes and coyotes are also doing well. Others have niches that are in direct conflict with human development. Larger shore birds (herons, cranes), amphibians and sea turtles (to name just a few) are seriously impacted when people start developing around their homes. In the cases of the birds and amphibians, proximity and/or building right on top of their habitat drives them out, while sea turtles experience lower fertility because ocean-front high rises make beaches too cool for their sand-buried nests. Finally there are some species that humans just do not like, either due to real or imagined impact on themselves or their livestock. Wolves are making a comeback after being hunted to local extinction (exterminated from a given area) because of the danger they posed to livestock. While reptiles such as snakes and crocodilians excite an unreasonable amount of fear, to the point that some areas of the US host “Rattlesnake Round Ups” in an effort to exterminate an animal that is more danger to the vermin around their trash than to them.

Seriously, why be afraid of snakes? They have the WORST aim.

Getting into how animals adapt to life in the big city (beyond the basics, like learning the bus schedule, finding the best cafes, etc), knowing the species of animal in question is as important as knowing how a particular population adapts. Different species have different lifestyles better suited toward adapting to urban environments. I will get into more detail on this in my next post.

Oh Baby

Today I would like to speak with you all about reproduction. Not sex or any of that fun stuff, procreation! Procreation is serious business. All organisms want to make a lot of babies and ensure that as many of those babies survive as possible. But how? Resources and time are limited so you can’t pump infinite babies out indefinitely and expect to be able to provide enough care that they all survive. Choices must be made. And by “choices”, I of course mean reproduction patterns. And by “made”, I mean evolved.

So organisms evolve these different reproduction strategies. At the heart of it, the strategies are based tendencies toward quantity or quality.

By the way, those are squid egg CASES. Meaning each of those holds hundreds of eggs.

 

Not too say that species tending towards larger quantities of offspring will then have lower quality offspring. No, it’s really a question of large quantity reproduction vs. high quality parental care. To get really technical, we say species are r-or K-strategists. “r” as in population growth and “K” as in carrying capacity. For my own memory, I find it useful to think of these as rapid reproduction vs. karing for the kids.

Species in unstable habitats with non-limiting resources (not unlimited resources, but resources where the amount or access to resource is not limiting to population growth) that can rapidly respond to disturbance and can experience rapid population growth are typically r-strategists. Habitat will limit population as opposed to competition within the habitat. Other typical traits of r-strategists include early and frequent reproduction with many offspring that have a high mortality rate. These species also tend to be small and semelparous (adults reproduce once and then die).

Conversely, species with growth limited by competition, in stable environments and that possess a slower growth rate will be K-strategists. K-strategists will live longer, but they will not reproduce as much or as early and offspring have much longer development. However, offspring survival is much higher due to extensive parental care and smaller “litter” sizes. These species also tend to be iteroparous; they’ll reproduce many times over their lifetime.

Of course, nothing in biology is set in stone. There are small starfish that brood over hundreds of eggs and large sharks that leave their young right away (life is unnecessarily hard for shark babies, but that is a tale for another day). So consider r and K reproduction strategies as on a spectrum. A spectrum with some little loops and fangly bits. Because life ain’t simple.

 

Sources

Bohn, K.M. 2011. “Life History Patterns”. Ecology. Whitman College. Walla Walla, WA.

Mustelid-day 3: Your Old/New BFFs

I swear that I am getting CRAZY stuff done when I’m not here. CRAZY. I swear.

Ahem…

Anyway! Where was I? Ferrets, right?

Right.

Of the three ferret species in the world, the black-footed ferret is the only one native to North America. And we kind of ruined its shit.

Formerly, our little (“little”, they can be up to two feet long) BFFs of the prairie, rocked the nights away (they’re nocturnal) on the mixed grass and short grass prairie scene. Literally. They are lively little suckers.

They are also really into the underground scene (they’re fossorial). Tunnels are their THING, man. Not their tunnels, though, prairie dog tunnels. Why tire your stubby little paws digging when a few hundred prairie dogs can do it for you? Exactly: Prairie Dog Construction Crew. Plus our BFFs can eat the crew when they’re done. But our BFFs depend on this kind of convenience; a pair ferret needs around 10,000 prairie dogs within its territory in order to survive. Good thing they’re usually solitary, but still; DAMN.

Now, to get at where humans come in to ruin everything. As farms blossomed on the lone prairie, many prairie dog towns were tilled into oblivion, and most of our BFFs with them. Where once there were hundreds of millions of prairie dogs, now there are, like, 20 million. A sizable dent in their numbers, but not so bad, eh? Well, the tilling that only dented the prairie dog population, endangered our BFFs. They now occupy less than 2% of their former range. Also, since there are still more than plenty of prairie dogs to go around, it means that those guys are running amok on the prairie. Their other predators are just not picking up the slack. Solution: captive breeding programs and reintroduction. Simple? NEVER. This kind of shit is never simple. Just ask a Montanan about wolves. Anyway, the issue is controversial because ferrets require prairie dogs (SO MANY PRAIRIE DOGS) and that means that the same people that want prairie dog population control will have to leave those P-Dog towns alone for our BFFs to do their thang. If this doesn’t seem like a big deal, imagine you are a rancher and prairie dog holes are breaking your cows’ legs. Yeah, it’s not going over well.

This isn’t to say there is not a solution! We just need to get along, and why can’t we all just get along? We have to, for our BFFs.

Sources

–. 2011. “Ferret Facts- Animal Profile.” Black-Footed Ferret Recover Program. Black-footed Ferret Recovery Implementation Team. August 1, 2013. < http://blackfootedferret.org/animal-profile&gt;

Cogger, Harold G., Joseph Forshaw, Edwin Gould, George McKay and Richard G. Zweifel. 2002. “Carnivores”. Encyclopedia of Animals. Barnes and Noble Books, New York.

Krebs, Candace. 2013. “Ferret’s Link to Prairie Dogs Underlies Opposition.” La Junta Tribune Democrat. August 1, 2013 < http://www.lajuntatribunedemocrat.com/article/20130726/NEWS/130729959&gt;

(A)Sexy Times

I LIVE! My statistics class is finished and I can write weird shit on the internet once more. Huzzah!

So let’s get right down to business. Not just any business, business, if you know what I mean. Right? RIGHT? Ya know…IT? The deed…? Sex. I’m going to talk about sex. Jeez, you guys are hard to fake talk to, may as well just talk to myself! Anyway, before the tittering (heh, “tittering”) begins, know that I will be talking about sexy times AND asexy times. That is, I’m comparing sexual and asexual reproduction. Bow chicka wow wow!

Now, although we’re waiting on input from single-celled organisms, plants* and…well, most animals, the consensus is that sex is pretty great. So that’s not a real consensus, sue me. But if you throw two sexually reproducing organisms in a room (maybe not actually throw them) and give them some alone time, they’ll make little sexually reproducing organisms and soon you’ll hear the pitter-patter of little genetically variable, possessive of good genes from both parents, feet. Independent assortment (Remember Mendel?) and random fertilization (the match up of different gametes with different chromosome combinations) makes for some incredible genetic variation potential. There are 8.4 million different chromosome combinations one gamete (sperm or egg) can possess, so that’s 70 trillion possible sperm/egg pairs, each with a unique combination of chromosomes. All the stuff about everyone being a miracle is true; each one of you was a one in 70 trillion chance. Unless you’re identical twins. Then you aren’t a miracle. You are a poseur.

All this variation means sexually reproducing organisms are (as a whole, not individually) completely prepared for environmental variability. They can evolve their way out of all kinds of shit. So sex is awesome! It results in genetic variability, the combination of good genes from each parent and word on “the street” is that it’s enjoyable, too. What’s not to like? EVERYTHING.

OK, maybe not everything, but the variation that makes sexual reproduction so good, can also be a big problem. Besides both parents contributing good genes, bad genes can also get thrown in and good gene combinations may be lost completely. In addition, it takes a lot of energy to find a mate and then reproduction is pretty slow. So what happens if you cut out the sex? Asexual organisms can reproduce by budding, division (only single celled organisms, but it’s funny to imagine koalas dividing) and parthenogenesis (two eggs mix in self-fertilization). Unlike sexual reproduction, the parent can pass on 100% of their genes and not worry about trying to get a date or bad genes from some lame baby daddy wrecking everything. Reproduction is also a lot faster. HOWEVER, without the genetic variability, asexual organisms can’t really handle variable environments, are susceptible to disease and can’t “lose” bad genes or gain better genes.

I say it’s a toss up. But HBO would be out of a job if we all went asexual, so may as well support the economy

 

Source

Bohn, K.M. 2011. “Sexual Selection”. Ecology. Whitman College. Walla Walla, WA.

 

*Yes plants have sex. Flowers are just colorful plant genitalia and “pollination” is just science slang for plant sex. Think about THAT next time you buy a bouquet for your sweetie.

Such lovely…flowers.

 

Foraging for Pizza

Last night I had crabs. Rather, I had crab legs. A lot of them. They were buttery and delicious and I promptly fell asleep after. But as my mom, dad and I struggled with extracting every last crabby morsel, I had to wonder how many calories I was losing just to get the ones hiding in the end of my crab leg (Yes, I actually wondered that, I can’t make up how nerdy I am). This is actually an important question in the wild; how to maximize one’s caloric intake with a food item while minimizing the calories and time lost obtaining and handling said item. Biologists call this optimum foraging.

Optimum foraging is based on the hypothesis that natural selection has driven animals to evolve foraging habits that maximize caloric gain per unit time. The factors driving these habits include environment, prey type (right now I will include plants as “prey”, considering those require handling and obtaining as well), availability of prey and anti-predator defenses of prey (armor, toxins, etc). These influence hunting/gathering time, as well as handling time (the time it takes to eat the thing). If it takes time, it will take effort, as a result, a prey item that takes a long time to obtain/handle or takes a lot of effort, better have a high caloric content. That is, it had better be worth it. There is an actual equation (for you math-heads out there) for calculating energy gain per unit time from a given prey item as equal to number of prey encountered (per unit time), multiplied by caloric gain and minus energy, with all that divided by one plus number of prey encountered times handling time.

How about a translation? Let’s say I only eat pizza. Because optimal foraging applies more for specialists (will explain more on that shortly), let’s say I don’t just order pizza, I have to catch the delivery boy and somehow wrest the pizza from his grasp. So we have these wandering delivery boys, and there are a lot of them carrying only one pizza, but a few are carrying 3 or 4 pizzas. Because I’m a crazed, pizza-eating fiend, I do not have a calculator to work out the math of which delivery boy would be more advantageous to chase. I rely on experience, and experience tells me that the delivery boys with one pizza are very fast, but they aren’t any faster than those with four pizzas and I have to catch a lot more of them before I’m full. My pizza-crazy mind can then conclude that it is much more worthwhile to pursue the fewer, but more pizza-laden, delivery boys.

Now, let’s say those multi-pizza delivery boys start carrying their pizza in wooden boxes (it’s weird, I know, work with me here!). They are now a little slower, but I have significantly more trouble in handling my pizza. As in real life, if you have a difficult prey item that is not absolutely impossible to deal with, natural selection starts favoring animals even a little more adapted to dealing with that prey. Those animals survive and reproduce better as a result and, many (manymanymany) generations later, you have a species adapted to catching and eating that prey item. That species is a specialist; they specialize with one particular prey item. Generalists are much less picky. They evolve foraging habits that maximize caloric intake with a broader category of prey item (like carnivores with live prey, scavengers with dead prey, frugivores with fruit prey, etc). So in the case of pizza-fiend me, I may not do so well with my armored pizza, but if I have any kids with bigger teeth or sharper nails, they will be better adapted and will eventually lead to a species particularly adapted to getting pizza out of wooden boxes. And they will be optimal foragers and I will be such a proud (greatgreatgreatgreat) grandparent.

 

 

On an unrelated note, I was going to ignore the fact I missed a post yesterday, but this is as good a time as any to bring up the fact that I will be reducing my blog updates to five times a week. Unforgiveable, I know, but this will allow for unexpected busy-ness and crab boils.

 

Source

Bohn, K.M. 2011. “Optimal Foraging”. Ecology. Whitman College. Walla Walla, WA.