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Thursday, November 29, 2018

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. 19th 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 21st 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.

Wednesday, November 21, 2018

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.

Thursday, November 15, 2018

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 3rd to 5th 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.



Thursday, November 1, 2018

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.