Species of the Month

Up on the rooftop click click click, down through the chimney it's the species of the month! Christmas is right around the corner, so it’s time for another festive species of the month. The caribou is the wild version of the domesticated reindeer. Santa’s herd is safe, but their wild counterparts face habitat loss and in some areas have been hunted to extinction.

Woodland caribou

Scientific name: Rangifer tarandus

Kingdom: Animalia (animals)

Class: Mammalia (mammals)

Order: Artiodactyla (even-toed ungulates)

Range: Circumpolar- Canada, northwestern US, Greenland, northern Europe

Habitat: Arctic tundra and boreal forest

Lifespan: 4.5 years on average

Diet: Leaves, bark, lichen, mushrooms

Predators: Bears and wolves

Conservation Status: Endangered (US), IUCN Species of Least Concern

Lighter colored tundra caribou (NPS)

Other Information: Caribou are the only deer species featuring antlered females. Not all females grow antlers, however. Male antlers are larger and more intricate. Males use theirs in sparring during the rut. Like other deer species, mating is controlled by a dominant bull who fends of younger challengers. The fights leave males injured and/or exhausted and vulnerable to predators. Domesticated reindeer have been used as beasts of burden and for food for thousands of years. There are several subspecies of caribou. Northern caribou are nearly white and smaller than their southern counterparts. In North America, the woodland caribou is a dark brown and critically endangered. Just a handful lived in the wild in Washington and Idaho. Recently, they were all captured and sent to a secure area in British Columbia to protect them from predators in the hopes that their population will increase. Caribou hooves are very large and concave, serving as snowshoes.

Caribou hoof (Where To Next)

The size and shape also aid in swimming. Caribou migrate long distances and must cross many rivers. When walking, they make a loud clicking sound, caused by a foot tendon rubbing on bone.

Information once again comes from the good people at Michigan’s AnimalDiversity Web.

Domestic reindeer (The Nature Conservancy)

A Christmas Comet

Just in time for the holidays Earth has a celestial visitor! Comet Wirtanen makes one of the closest approaches ever recorded. It’s a small comet with a short orbital period of 5-6 years. It is bright enough to see with the naked eye, although because of its small size the way it scatters light, it is hard to spot. Keeping with the holiday tradition, if you’re lucky enough to see it, it will appear to be green.

Wirtanen approaches, as seen in November (NASA)

I am sadly surrounded by street lights, so I had to take a short trip to a state park where I had a dark sky. With a spotting scope and a general area of where to look, I was unable to find Wirtanen. The comet makes its closest approach to the sun tonight, and I decided to try again. However, I’ve been blessed with clouds. My next chance is Saturday night, when it is closest to Earth. Of course, rain is in the forecast.

Geminids (Smithsonian Magazine)

While I failed in my attempt to see just my second comet, I happened to see a meteor streak across the sky. Meteor showers are bits of cometary debris burning up in the atmosphere as Earth passes through the comet’s debris field. Comets are just dirty snowballs that melt a little bit as they approach the sun. As they break up, all the pieces that break off trail behind and wait for our orbit to sweep them up. This meteor was not associated with Wirtanen. It was part of the Geminid meteor shower, which is debris from the comet 3200 Phaethon, a dead comet. Its ice has melted and all that remains is rock. Most likely, if we ever pick up all the debris then there will be no more Geminids.

If you want to try your luck at finding Wirtanen, here’s a handy link that shows its location throughout the month. This month's information is from StarDate and NASA.

Habitat Rehab

Habitat restoration is one of the most important challenges facing conservationists today. Without adequate habitat, endangered species can’t be recovered. Many human activities require restoration as well. Fully functioning wetland systems can provide flood control and clean drinking water. How does the process of habitat restoration work?

Restored coastal marsh, where dikes were removed to
allow the sea to once again access the land

The first step, as in medicine, is “First, do no harm.” A site evaluation will determine exactly what needs to be done to restore what once was. Noting current conditions establishes a baseline for measuring success of the project. It might involve stabilizing a feature immediately, such as an eroding stream bank. After figuring out what needs to be done, the next step is figuring out how to do it.

In many cases, conservationists will use a reference site similar to what is being restored to determine plants and other features. Plants will influence what kind of animals will begin using the site, but the land and water on the site will determine what plants can live there.

Live willow stake planted to reforest
a former pastureland

A lot of times, restoration work is more than simply replacing plants and animals that lived on a site before people came in and messed it up. A site I monitored in Washington had once been a thriving salmon stream with a wide flood plain. 19^th century farmers drained the area by straitening the stream to allow water to flow in and out faster. They also cleared the trees. Fast forward to the 21^st century, and we’ve figured out that the stream needs to be slowed and shaded. Over a period of several years, the curves were put back in the stream and thousands of new trees and shrubs were planted. Fixing the stream required building temporary dams, removing fish by hand, and using heavy equipment to excavate a new stream bed at just the right depth and slope.

Ohop Creek after being restored to its twisted ways

After work has been completed, the site must be monitored for success. There should be some kind of measurable goal, and even if the restoration fails it can be a lesson for future attempts. The site I mentioned was restored for salmon habitat, and while it will take a few years for trees to begin cooling the water temperature, it has been under constant observation since work began. Several times a year, conservation groups involved in the restoration work check water levels, tree survival, how many salmon are spawning, and what kinds of animals are using the habitat. All of this is checked against initial observations from before the project began.

This prairie, currently a restoration work in progress,
was a field of weeds a few years ago

My work with habitat restoration has been monitoring (documenting wildlife and animal signs, as well as plant survival rates), site maintenance, and invasive species removal. The work is hard and sometimes conditions are brutal, but I find it to be very rewarding.

In many cases, restored habitat is second rate compared to what it once was and what nature has provided. It’s not for a lack of trying, but nature is a much better architect of natural features than what man could ever hope to be. But it’s better than nothing.

Species of the Month

Don’t laugh at November’s Species of the Month. Although it lends its name to the fiction hometown of the Griffin family in TV’s The Family Guy, the northern quahog (pronounced co-hog) is a real animal. A species of clam, it was likely eaten at the first Thanksgiving in 1621. The Pilgrims neglected to save a menu for posterity, so we’ll never know for sure. Will your Thanksgiving meal include any seafood? 

Northern quahog (NOAA Fisheries)

Scientific name: Mercanaria mercanaria 

Kingdom: Animalia (animals) 

Class: Bivalva (bivalves) 

Order: Veneroida (saltwater and freshwater molluscs) 

Range: East coast of North America from Gulf of St. Lawrence to Gulf of Mexico 

Habitat: Estuarine intertidal mudflats 

Lifespan: 30 years or more, a separate Arctic species was found to be 507 years old 

Diet: Zooplankton and phytoplankton 

Predators: Moon snails, oyster drills, whelks, rays, skates, shorebirds, humans 

Conservation Status: No special protection. 

Northern quahog (Chesapeake Bay News)

Quahogs are commercially harvested. In addition to a food source, they act as a natural filter by feeding. They filter feed through a siphon that extends from the shell. Plankton and pollutants go in, clean water comes out. Quahogs are mobile, although they don’t move much. A single foot at the base of the shell holds it in place in the mud or sand and can quickly dig in to avoid predators. It can also be used to move laterally. Quahogs reproduce by releasing sperm and egg cells into the water, where they randomly meet and fertilize. Within two weeks, the quahog larvae have formed a foot and shell and anchored to the substrate. Ocean currents aid in fertilizing the eggs and dispersing the larvae. This week's information comes from University of Michigan's Animal Diversity Web.

Ancient Trees

When you think of ancient trees, you probably think of petrified wood. You may be shocked to know that there are some ancient trees that are still living. The oldest known living organism is a bristlecone pine in Nevada that is over 5000 years old. When this tree sprouted, writing was a new concept and Egypt was under the rule of its first pharaohs. In fact, the pyramids weren’t even built yet, although Stonehenge was an active construction site.

Bristlecone pine (US Forest Service)

Other ancient trees are the giant sequoias of California in the 3000 year old range and limber pines date back to the 3^rd to 5^th centuries. East of the Mississippi, the oldest tree is a northern whitecedar in Ontario, which was just a gangly teen of 1100 years old when Columbus sailed the ocean blue. Other trees around the world are estimated to be over 3000 years old, with a yew in a Welsh churchyard that might come close to 5000 years old.

Limber pine

None of those ancients come close to the ages of some cloned trees. Clones are genetically identical to the parent tree. Rather than germinating from a seed, they grow from the parent tree’s root system. Genetically identical Huon pines in Australia are estimated to be 3000 years old. Norway spruces in Sweden, which normally live to be about 600, are growing from live roots that are estimated at 9000 years old.

The king of ancient trees is the Pando in Utah. The Pando is a grove of quaking aspens with about 47,000 trees growing from a single root system. The individual trunk parts of the aspens average 130 years old, but the entire system is estimated to be anywhere from 80,000 to a million years old. The heaviest known organism in the world, the Pando recently made headlines because it is dying. Like so much else in the world, the cause of death is human activity.

The Pando (Smithsonian)

This week's information comes from Wikipedia, of all places. Not to be trusted as a reliable source, it's a great place to find lists.

Daffy Ducks

This week, let’s have a look at one of my favorite critters, ducks. Mallards are probably one of the most common birds in North America. There have always been a lot of them near me, whether I was living in Pennsylvania or Washington. Many species are migratory, but my mallards are year-round residents. Growing up, I could always count on a few in the back yard, as we had a small stream separating us from the town park.

A pair of ducks swimming in a stream

There are two kinds of ducks- diving ducks and dabbling ducks. Diving ducks, as the name implies, dive underwater for food. Dabbling ducks like the mallard flip their butts in the air and their heads in the water to find food, but remain afloat. Different species have different food needs, but as a group they feed on fish, insects, worms, mollusks, and plants.

A mallard (a dabbling duck) goes bottoms up for food

A Barrow's goldeneye (a diving duck) beginning a dive

Females lay eggs in a nest, then lead their hatchlings to water. One year, a mallard nested in a tree in my parents’ yard. It’s a common practice among wood ducks, but at the time such behavior was unknown to me or anyone else in town. City workers came and got the ducks out of the tree. They didn’t believe it until they saw it. Ducks with tree nests usually nest right above a body of water. After hatching, the babies will plop out of the nest into the water, following mom’s lead.

Wood duck hatchlings leaving the nest (Pintrest)

One thing I’ve been guilty of in the past is feeding the ducks. Since they were frequent visitors, and because no one likes the end piece of bread, I would tear it into little pieces and toss it to the ducks. Bread isn’t part of a duck’s natural diet and can lead to health issues down the road. It’s better to let wildlife be wild and not count on people for food, but if you must feed the ducks, give them grape halves.

Mother mallard and babies

Ducks are known for their stereotypical quacking, but that sound belongs to the female mallard alone. She seems to be especially noisy in a large group of ducks. Probably the best duck sound is the mutter. I notice this if I’m on a bridge or at the water’s edge and a duck swims by. They sound to me like they’re muttering something under their breath at me. My favorite duck behavior occurs during mating season. On many occasions, I’ve seen half a dozen or more males chasing a female around the back yard. There’s nothing like a bunch little footballs with heads waddling around as quickly as possible.

Maybe you see a lot of ducks in your area too. Are they so common as to become almost invisible? Slow down and take the time to watch them.

Species of the Month

Halloween is right around the corner, so it’s time for another creepy crawly species of the month. We’ve covered bats and owls, so this year we’ll go to the spiders. Stop reading here if they creep you and come back next week. Grass spiders are a genus of several funnel weaving spiders, including the Pennsylvania grass spider. You’ll likely start noticing these robust spiders in your house as they venture inside to avoid the falling outdoor temperatures. We associate spiders with Halloween because they are at their biggest after growing all year.

Pennsylvania grass spider at my sister's house

Scientific name: Agelenopsis species

Kingdom: Animalia (animals)

Class: Arachnida (arachnids)

Order: Araneae (spiders)

Range: All of North America except Arctic areas

Habitat: Lawns, your house during fall

Grass spider in its natural habitat (Penn State)

Lifespan: One year

Diet: Insects

Predators: Birds

Conservation Status: No special protection

Grass spider in its web (Missouri Department of Conservation)

Other Information: Grass spiders build funnel or tunnel shaped webs in the grass, hence the name. Females lay eggs in sacs during late summer or early fall, with eggs hatching in spring. The eggs survive over the winter but adult spiders do not. Grass spiders are fast and typically avoid humans, but will occasionally bite with trapped and threatened. Information this week comes from Insect Identification, despite spiders not being an insect.

Symbiotic Fish and Forests

With the arrival of fall, salmon spawning is in full swing in the Pacific Northwest. Being a fish, they obviously interact with a lot of other sea creatures and aquatic life. They also have a symbiotic relationship with the forest, believe it or not.

Fish and forests, at first glance, are as different as, well, fish and forests. But despite being a water-based critter and chunk of land, they interact with each other splendidly. They feed each other. I’ll explain how, starting with the how the forest helps the salmon.

McClane Creek, an example of healthy salmon habitat

Forest trees are crucial to salmon habitat. Despite living in a river for part of their lives, salmon lean heavily on trees for survival. Salmon need cool, clean water. The forest keeps the river clean by slowing the flow of surface water and the sediments it carries. Sediments can clog their gills and cover the rocks where they lay their eggs during spawning. Shade from the trees keeps the water temperature at acceptable levels during the summer. Warmer water loses dissolved oxygen, and salmon are very picky about temperatures.

Pink salmon returning to the cool, shaded water of Nisqually River

Fallen trees in the river create habitat diversity. The large woody debris forces the current to change, creating deep pools on the downstream side of the obstruction and changing the complexity of the stream bed. The deep pools provide a place to hide from predators and respite from high flows during the rainy season. The large woody debris adds nutrients to the ecosystem as it decomposes. It also contains or attracts tasty insects for the salmon to munch on.

Artificial logjams like this are used as habitat enhancement
in salmon streams.

The salmon help replenish the forest by provided nutrients (nitrogen in particular) from the sea when they die. Predators are the immediate beneficiaries of the ocean’s bounty, but the forest as a whole benefits. Plenty of leftovers decompose both in the river and on land. As the fish decomposes, or after a bear poops in the woods, the trees and other plants absorb the nutrients so they can continue to give back to the salmon and the cycle continues for another season.

Salmon bones replenishing the Hoh Rainforest

It was once thought that removing obstacles like large woody debris was an improvement to the riparian habitat. Now we know better. In some areas, workers are dropping downed trees into rivers. In others, engineered logjams do just as well. Watch this short video about riparian restoration for the benefit of salmon and flood control in Oregon.

Superfund Site

While I was working toward my environmental science one of my classes was Environmental Law and Policy. For one of our assignments we had to research a Superfund site and present to the class. The site I chose was less than a mile as the crow flies from where I grew up. At that time, EPA hadn’t begun work on the site. Last year after moving back to Pennsylvania, I attended an EPA meeting on the status of the cleanup. This year, as work nears completion, I was able to tour the site with EPA’s Tim Gallagher.

Contrary to what you might think, not all Superfund sites are full of leaking drums of glowing green radioactive waste. The Watson-Johnson property was a landfill from the 50s to the 70s, then forgotten about. In the late 90s, water testing revealed several contaminants in the groundwater. One of the town wells for the water supply was closed. The solution the EPA came up with was to cap the landfill and use chemical injection to neutralize the contaminants in the groundwater.

Watson Johnson landfill site. The geosynthetic is
buried under 18 inches of soil here.

Capping the landfill is a common practice at sites like this. Why not remove the waste? Odds are, everything would just be taken out of the ground and buried in another landfill somewhere else. One oozing container was discovered and removed from the site, but otherwise it was all collected together and capped. The cap uses a layer of compacted clay soil, a waterproof synthetic fabric, more soil, and vegetation. The purpose of the cap is to keep the waste contained and keep water out, preventing anything from seeping into the groundwater.  Water drains to wetlands, ponds, and level spreaders. Level spreaders are cement cisterns that capture water and allow it to overflow and slowly spread away from the site.

Drainage swale around the outside of the capped landfill.
Grass seed has already been spread inside it.

Level spreader beyond the edge of the capped landfill

The soil above and around the cap is contoured to divert surface water away from the cap. There are natural wetlands on site, as well as new artificial wetlands created to contain and disperse runoff. The cap itself layered in a way that creates pathways for gases flow towards several vents. Because they site was once open but now is closed with those release points, concentrations are higher. Methane has been noted at the vents, but not volatile organic compounds (VOCs).

Gas vent. No monitors are attached.

Monitoring and injection wells reach the groundwater. Sodium permanganate is injected to react with the chemicals in the water. The reaction breaks down the chemicals (including the sodium permanganate) into harmless elements like oxygen and hydrogen. Monitoring wells are set up to test the levels of chemicals in the water. Injections will stop once the concentration goes below 100 parts per billion. At that point, EPA will begin bioremediation. Microscopic critters that eat the contaminants will be injected to the groundwater to bring the contaminants down even further.

Work on the site is nearing completion. Despite a cold winter and rainy summer, work is only two months behind schedule. Workers are currently adding a layer of topsoil six inches deep on top of the cover soil. Once topsoil is in place, it will be seeded with native grasses. Around the cap, workers are setting up deer fence to protect new trees that will be going in. Landscaping was supposed to start last week but was delayed by heavy rain.

EPA will continue to monitor the site for a year after completion, before turning that duty over to the state. Future plans include nesting boxes for swallows and bats. The new trees will create a nice matrix with the older existing woods on the edge of the site, which should attract songbirds that prefer new growth. The site is privately owned, so it will not become a park like old landfills in other areas. However, development will be limited by cap so it will likely remain a nice green oasis as the area becomes increasingly more urbanized.

For more information visit the EPA's Watson Johnson website. Special thanks to Tim Gallagher for taking time out of his day to show me around.

Firefly Watch

I participated in an ongoing citizen science project over the summer. Firefly Watch was formerly run by Boston’s Museum of Science, but was run by Massachusetts Audubon this summer, my first with the program. The goal is to monitor firefly populations by counting the number of flashes in three periods of ten seconds. Colors and flash patterns, as well as date, time, weather conditions, and site conditions are all recorded. I signed up for this because fireflies were always a highlight of the summer when I was a kid, and later when my own kid was little. 

Having been away from my ancestral home for a decade, I had no knowledge of local population trends other than my mom telling me she never sees fireflies anymore. That was disturbing to hear. So twice a week I went to my parents’ house starting in late May to see if they had any fireflies left. The first ones showed up on Memorial Day, right about when I remember them first arriving. They were few and far between for the first two weeks or so and peaked around the 4^th of July. I decided to keep up the watch until I had two consecutive shut outs, and expected to be done the first week of September. 

However, the last firefly I recorded was on September 24^th, later than I’ve ever seen one. In fact, I only remember seeing them in September once before, and they came a month late that year. To top it all off, I saw another on September 28^th during the day while away from home. However, to be consistent I only counted observations at one site. To me, it isn’t helpful to track population trends if I am not tracking at the same location, at least in this case. For something larger with a wider range I would, but these little guys don’t roam very far. Since this was my first field season I have no data to compare with, but I plan on being back. Hopefully all I’ll see is positive trends!

Feel free to sign up for Firefly Watch next year!

Deciduous Decisions

In the plant world there are two types of trees: deciduous and evergreen. Deciduous trees give us spectacular displays of fall color before shedding their leaves. Evergreens provide a shadow of summer with a splash of green during the bleak winter days. Both types of trees use the leaves (broad leaf or needle leaf) for photosynthesis, but obviously the deciduous tree evolved to opt out of photosynthesis during winter while the evergreens evolved to work a longer season. Which tree has the competitive advantage until the spring greenup?

Life in the wild is all about two things: making babies and being energy efficient. Depending on the environment and situation, being deciduous or evergreen offers a competitive advantage by saving energy, but of course it also comes at a price.

Deciduous trees typically live in areas with temperature fluctuations. Here in the northeast, we have a nice mix of deciduous trees: maples, oaks, hickories, poplars, and more. We also have four distinct seasons. Winters can be snowy, and for a tree that spreads it branches quite a distance from its trunk, not having leaves to catch a heavy snowfall could be the difference between losing limbs or not. Evergreens compensate for snowfall by having a conical shape and shorter branches, with the longest at the bottom. The branch structure allows snow to fall to the next level of branches relatively quickly.

Summer deciduous

While the loss of leaves saves branches, it costs the tree energy. A tree must have enough energy stored up for next spring’s new leaves by fall. Because photosynthesis uses energy (much like chewing and digesting your food burns calories), deciduous trees evolved to shed leaves when there is less sunlight, not enough to be worth the energy expense to generate some more energy. While the deciduous trees are standing idly through the winter, evergreens take advantage of their ever green leaves (either needles or broad leaves in the tropics) and photosynthesize for a longer season or year-round in the tropics. They gain a little more energy that way, and we’ll see why next.

Late fall deciduous

Those expendable deciduous leaves are fairly flimsy compared to a pine needle or palm frond, which are built to last. Less energy is required to build a full set of maple leaves than pine needles. More of the maple leaf is dedicated to photosynthesis than a pine needle, which needs more compounds for structure and defense. Unit for unit, a maple leaf generates more energy than a pine needle. Evergreens, conifers especially, use that conical structure to capture more sunlight to maximize energy production.

Summer evergreen conifers

Deciduous trees thrive in nutrient-rich soil. If there are plenty of nutrients to absorb, they can afford to shed leaves. They often draw remaining nutrients from the leaves back into the trunk before shedding leaves. They even contribute to the nutrient cycle with their fallen decaying leaves. Evergreens have adapted to nutrient-poor soil. They keep their leaves because of a lack of available nutrients. If you look at how green and full of life the tropical rainforests and dense forests of the Pacific Northwest are, you may be shocked at how poor the soil actually is. The nutrients are usually absorbed right out of the dead material into the upper layer of soil and into the living trees.

Winter evergreen conifers

The different leaf styles also lead to different strategies for water conservation. When stressed due to dry conditions, deciduous trees will shed their leaves early to stop water loss. During photosynthesis, water is drawn from the roots to the leaves to make it happen, and the trees exhale water vapor. Evergreens keep their leaves, but they have a waxy cuticle on them that helps prevent water loss.

Hopefully you have a better understanding of why trees do what they do. With fall here and winter on the way I think we can appreciate both leaf styles for the splashes of color they give us. How is the leaf situation in your neighborhood?
This week's information comes from an article by Frances C Smith in the journal Maine Naturalist. 
Frances C Smith: Smith, F. (1993). Evergreen vs. Deciduous Woody Plants: Which Wins Where. Maine Naturalist, 1(4), 205-212. doi:10.2307/3858181 

Migration

The days are getting shorter and cooler. Leaves are starting to turn and fall. Winter is approaching, and many animals are have already begun their seasonal migration. While some hibernate to avoid unfavorable seasonal habitat conditions, others move temporarily to more suitable habitat.

Migrations occur across all different animal classes: birds do it, and so do mammals, fish, insects, reptiles, amphibians, and crustaceans. Even some people do it. Florida and Arizona get plenty of snowbirds from up north every winter. More traditionally, nomadic tribes still exist in Africa and Asia living as they have for centuries.

We’re an ecology blog, not an anthropology blog so let’s forget about nomads for a minute. Perhaps the most visible migrations here in America are those of birds and monarch butterflies. Birds migrate to and from pretty much everywhere. Some stay within North America when migrating while others fly from pole to pole. Others, of course, are somewhere in between.

We’ll use the Baltimore oriole as an example of avian migration. They arrive in the eastern US from Central and northern South America in April and May. This is their breeding ground. They begin nesting right away and eggs usually hatch in June. Southern migration begins as early as July and has peaked by September.

Baltimore oriole (NPS)

Monarch butterflies journey to Mexico in a multi-generational migration. Northern monarchs go south to the oyamel fir trees in the mountains of central Mexico. Millions of them cover the trees. After winter, they head north again, laying eggs on milkweed plants. Caterpillars hatch in a few days and eat the plants before forming a chrysalis. A new butterfly emerges and continues the northward journey, stopping at milkweed to lay eggs and start the hatching and migrating process over again. The northernmost monarchs are able to return to Mexico in a single journey.

Monarch butterfly

The pronghorn in Wyoming migrates vertically. It moves from summer grounds in Grand Teton National Park about 150 miles south to lower elevation in the sagebrush habitats of the Green River area. This is North America’s longest mammal migration.

Pronghorn

Not all migration is seasonal. Zooplankton in the ocean migrate vertically through the water column on a daily basis. At night the move toward the surface, and by sunrise they are headed back to the briny deep. While a journey of hundreds or thousands of feet might not seem like much to you, keep in mind that these tiny critters probably can’t see as far as the other end of a yardstick.

Zooplankton (Nature International Journal of Science)

Fall migration is happening now. Who is moving through your neck of the woods?

This week's information comes from:

Journey North (Baltimore oriole)

National Geographic (monarch butterfly)

Wildlife Conservation Society (pronghorn)

Nature International Journal of Science (zooplankton)