The Temperate Rainforest

Climate:

The obvious element of climate in the temperate rain forest is precipitation.  At least 200 cm of it, perhaps up to 350 centimeters in warmer areas.  The precipitation can fall in the form of rain or snow, with snow becoming more likely at higher elevations.  The average annual temperature is above 0 C, largely influenced by the nearby ocean.  The warmest of the temperate rainforests may have average annual temperatures around 20 C.

 

 

 

 

 

 

 

 

World Distribution:  

This is a small biome in terms of area covered.  The main stretch of this habitat is along the northwestern coast of North America from northern California though southern Alaska.  There are also small areas in southern Chile, New Zealand, Australia and a few other places around the world, most of which don't show up on the scale of the map to the right.  In general, such forests form were relatively warm offshore waters affect inland climates.

Temperate Rainforest Distribution

      

 

Indicator Plant Species:

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

 

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Big coniferous trees dominate this habitat, including Douglas fir and Western red cedar, Mountain hemlock, Western hemlock, Sitka spruce and Lodgepole pine.  In addition, a number of deciduous trees are found here, particularly in warmer spots.  One of these is Big-Leaf Maple.

In addition to the trees, mosses and lichens are very common, often growing as epiphytes.  Epiphytes are also common in tropical rain forests; the common denominator is the moist environment that puts minimal water stress on plants without roots.

In the pictures here you can see Douglas Firs in the photo above.  The photo above right shows a ground-level view of the mossy forest floor, while the two lower photos to the right illustrate the epiphytes - mosses and lichens - that make a southern temperate rainforest home (note the deciduous trees).  Below is a species of Indian Paintbrush growing in a temperate rainforest in British Columbia.

Hoh River Rain Forest

Hoh River Rain Forest

Indian Paintbrush - Castilleja sp. - Chilliwack River Provincial Park, BC

Indian Paintbrush - Castilleja sp. - Chilliwack River Provincial Park, BC

Hoh River Rain Forest

Hoh River Rain Forest

Bigleaf Maple  - Acer macrophyllum

Indicator Animal Species:

Slug, Vancouver BC

Slug, Vancouver BC

Slug, Chilliwack River Provincial Park, BC

Slug, Chilliwack River Provincial Park, BC

While mammals are certainly found in this biome, we have seen many of them (deer, bears, coyotes, etc.) in other biomes.  I thought I'd focus on a few other species here.

You can't go to the Pacific Northwest without encountering a diversity of slugs.  These shell less gastropods are very much at home here; the humid air prevents desiccation (although I well remember encountering banana slugs on early morning jogs in Los Angeles; they are able to live in that desert city thanks to well-watered lawns).  The longer of the antennae have eyes at the ends of the stalks and the slug itself secretes a trail of slime (not unlike some po - wait, I'm not going to stoop to that joke here, it's too easy).   The slime helps it crawl and protects the soft underside from sharp objects.

Below are two birds from the temperate rainforest.  Clark's Nutcracker is at home high in the mountains of the west (not just in the temperate rainforests), but it will be found at high elevations.  The Blue Grouse is a northwest endemic.  When I wanted to confirm the ID on this photo I emailed Julie Zickefoose, a noted wildlife illustrator and writer, and she confirmed the ID stating that it would be a life bird for her (that is, if she had seen it, it would have been the first time, or in other words, she has not seen one personally in her life.  For me, getting a life bird on Julie is like, well me getting a dunk on LeBron James (who went to the same high school as my dad, BTW).  Look below for more on this bird... (Now Julie will be really jealous as I didn't share the rest of this story with her...)

Banana Slug, Ariolimax columbianus, Hoh River Rain Forest

Banana Slug, Ariolimax columbianus, Hoh River Rain Forest

Blue grouse - Dendragapus obscurus  - Chilliwack River Provincial Park, BC

Blue grouse - Dendragapus obscurus  - Chilliwack River Provincial Park, BC

Clark's nutcracker Nucifraga columbiana - Mt. Rainier, Washington

Clark's nutcracker Nucifraga columbiana - Mt. Rainier, Washington

Ecological Notes:

As with the tropical rain forest, water is the main story here.  As we have seen, the high humidity means that epiphytes are much more common here than they are in the drier temperate deciduous forest.  Also, plants like mosses and ferns, which rely on water for reproduction, are also common here. Because the climate is colder than a tropical rainforest, however, there is a major change in the makeup of the species.  Evergreen broadleaf trees are replaced by evergreen conifers, which are better adapted to shed snow and to photosynthesize in cold temperatures.  With this turn to coniferous trees comes a reduction in biodiversity as opposed to the tropical rainforest.  A small plot in the tropics can hold hundreds of tree species, comparable to all of North America including the temperate, boreal and temperate rain forests. Likewise, there are considerably fewer animal species in the temperate rainforest compared to its tropical kin.  This reduction in the number of species as one moves from the tropics to the poles is a global phenomenon, and is not restricted to the temperate rainforest; the temperate deciduous forest likewise has fewer species than a tropical forest, and the boreal forest and tundra biomes house fewer species still.

Tropical rainforests are noted for the rapid nutrient cycling that occurs on the ground.  In the tropics, leaves fall and decompose rapidly.  The roots of the trees are on the surface of the soil, and form a thick mat which absorbs the nutrients before they reach the soil (or before the rain can carry them away).  The presence of roots on the surface is a common phenomenon in all mature forests; trees that come along later in succession win out in competition for nutrients by placing their roots over top of the competitors, and this pattern is seen in the temperate rainforest as well.  What does not occur in the temperate rainforest, however, is a rapid cycling of nutrients.  Because of the cold conditions and the acidity released by decomposing coniferous needles on the forest floor, decomposition is much slower.  More of the nutrients are found in the soil here than would be the case in a tropical forest, although like the tropical forest most of the nutrients are held in the plants and animals themselves.

Threats:

The trees that make up the temperate rainforest are huge, and their value as timber is proportionate to their size.  With forests elsewhere already cut, there is tremendous pressure to log in temperate rainforests.  Thus, timber cutting is the number one threat to these forests.  It should be noted that timbering can be very difficult here because of steep mountain slopes.  If not done carefully, soil erosion can result; the end result of this is seen in the photo below, which shows the Fraser River in British Columbia entering the Pacific Ocean near the Vancouver airport carrying a heavy load of silt.  The silt, and the nutrients and pollutants it carries, are a threat to nearshore marine organisms as well as freshwater organisms in the river itself, and the area the silt is coming from can't be too pretty either.  A lot of criticism is leveled at 3rd world countries who allow their forests to be logged without regulation; Canada, a 1rts world country has also come under criticism for this (although most of the decisions on logging are made at the provincial level; and who is the US to criticize, having cut down most of our forests?).  The links below will give you some perspective:

http://archives.cjr.org/year/93/6/logging.asp

http://www.oldgrowthfree.com/bc_snapshot.html

http://www.wildernesscommittee.org/

http://www.for.gov.bc.ca/dck/

http://www.britishcolumbia.com/information/details.asp?id=36

http://www.cofi.org/

http://www.homedepot.com/HDUS/EN_US/corporate/corp_respon/faq.shtml

The map above shows the logging in just one area of British Columbia.  Click on the map for a full-sized view and explanation.

 

Tour:

Fuligo septica, Ohio

Fuligo septica, Ohio

Fungi are the most important decomposers in many ecosystems, and the temperate rainforest is no exception (warning: not all of these fungi were actually seen in a temperate rainforest).

In any forest, the predominant biological molecule is cellulose, which is basically a chain of sugars linked in a way that makes them particularly difficult to separate.  Indeed, only a few organisms, mostly fungi and bacteria, have figured out how to break down cellulose, and if it weren't for them tree trunks and leaves would never decompose and their nutrients wouldn't be returned to the soil.  Bracket fungi, above and to the right, are found on standing trees that are dead or in the process of dying.  Most of the fungus exists as small strands or mycelia that work their way through the rotting wood, digesting the cellulose and other components.  It is interesting that the presence of the fungus actually increases the nutritional value of the rotting wood, since the mycelium contains more readily digestible carbohydrates (compared to cellulose) and an increased number of proteins as well.  This increased nutritional value increases the number of insects feeding on the decaying wood, and the increased number of insects draws in woodpeckers.  In any event, at some point the fungus grows large enough that some of the strands make their way to the outside of the tree and form the fruiting body that we see here.  From this point high on the tree spores are released to hopefully find a tree of their own to recycle.

Above right:  An acellular slime mold, Fuligo septica.  This organism starts out as individual ameboid cells that crawl about feeding on bacteria.  If conditions are right, they fuse to form a multinucleate mass which continues to crawl around eating bacteria.  When they reach a critical size they come to the surface and form a fruiting body.  It usually starts off bright yellow and fades to a pinkish color that my colleague Dr. Almuth Tschunko describes as "dog-vomit pink".  This slime mold has a worldwide distribution, though most of us see it in our mulch beds.  

Other fungi form intricate fruiting bodies as well, and many of these draw insects, especially beetles and flies.  The fungus to the right below is one of these; the little black specks are beetles.  The cup fungi below is probably Peziza violacea, which also has a worldwide distribution, at least in the northern hemisphere.  It is known to grow in areas where there have been fires; to be honest I don't recall evidence of a fire where this picture was taken, and the background isn't much help.

 

 

Chilliwack River Provincial Park, BC

Peziza violacea?? Chilliwack River Provincial Park, BC

Peziza violacea?? Chilliwack River Provincial Park, BC

Red Columbine (Aqilegia formosa) Chilliwack River Provincial Park, BC

Red Columbine (Aqilegia formosa) Chilliwack River Provincial Park, BC

Pacific Bleeding Heart  (Dicentra formosa)

Pacific Bleeding Heart  (Dicentra formosa) 
Chilliwack River Provincial Park, BC

Some flowers from the rainforest.  To be honest, many of these have a pretty wide distribution, we saw bunchberry, for instance, in Maine on our 1998 trip.  Still, in the lush greenness of the temperate rainforest any color stands out, particularly on a drab, drizzly day.

Red Columbine (Aqilegia formosa)

Red Columbine (Aqilegia formosa)

Queen's Cup (Clintonia uniflora), Chilliwack River Provincial Park, BC

Queen's Cup (Clintonia uniflora), Chilliwack River Provincial Park, BC

Bunchberry, Cornus canadensis Chilliwack River Provincial Park, BC

Bunchberry, Cornus canadensis Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Blue grouse - Dendragapus obscurus  - Chilliwack River Provincial Park, BC

Blue grouse - Dendragapus obscurus  - Chilliwack River Provincial Park, BC

Blue grouse - Dendragapus obscurus  - Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Back to birds and slugs...  The Blue Grouse we encountered at Chilliwack wasn't alone - it was leading several of its chicks (above) as it tried to cross a road, impeded somewhat by 7 of us piling out of a van and taking pictures of it.  I didn't tell Julie about the chicks, now she'll be REALLY jealous.  To the left is a raven; Julie thinks it is a juvenile.  This one was in the forests on the lower slopes of Mt Rainier.  Ravens are one of the characteristic birds of the northwest.  Below are two views of the banana slug; this one was crawling over moss in the Hoh Rainforest of Olympic National Park in Washington.  This was not a particularly large or yellow specimen; I have seen them big enough and yellow enough to consider putting them into a banana split, which probably wouldn't be a good idea.

The Varied Thrush, below, is sort of a coniferous robin, that is, it is a ground-feeding, worm-hunting bird.  Not really restricted to the rainforest, it is also found there.

Banana Slug, Ariolimax columbianus, Hoh River Rain Forest

Banana Slug, Ariolimax columbianus, Hoh River Rain Forest

Banana Slug, Ariolimax columbianus, Hoh River Rain Forest

Banana Slug, Ariolimax columbianus, Hoh River Rain Forest

Varied thrush Ixoreus naevius  - Mt. Rainier, Washington

Varied thrush Ixoreus naevius  - Mt. Rainier, Washington

http://www.shim.bc.ca/chilliwack/main.htm

 

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Let's go on a field trip!  In 2004, I attended the North American Benthological Society (NABS) meeting in Vancouver, British Columbia. This is an international society of people who study freshwater ecosystems; technically "benthos" refers to organisms living on the bottom, but the Society has expanded its vision somewhat from its origins as the Midwest Benthological Society in the late 1950's.  After the meeting, a local fisheries biologist, Jordan Rosenfeld (above) took a group of us up to the Chilliwack River to hike in a virgin temperate rainforest on the US/Canadian Border.  If you look at the maps above you can see where we went.  We were basically able to drive around Lake Chilliwack  to the northernmost (top) extent of the topo map.  We then got out and Jordan fixed us some tea as we prepared our lunch, bought in a Vancouver grocery (I must admit that their dried seaweed aisle was a lot better than the one at our local Kroger's in Marietta).  The road was blocked at this point, so we hiked on around the lake (follow the orange dots in the image next to the topo map above) to the end of the lake and up the Chilliwack river (right).

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

As you can see, it was a gray day, with cool temperatures and a bit of drizzle, but what better conditions to experience a temperate rainforest for the first time?  You can see in these pictures the essentials of the ecosystem - the tall conifers, the thick mosses, the slowly decaying logs on the ground (some of these pictures were taken near the road, where, obviously some logging had taken place. 
Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

The Chilliwack River and its tributaries were constant companions as we hiked; we were never far from at least one of these.  What you see here are smaller streams is larger beds; these pictures were taken after the height of snowmelt.  Each year the rivers reach much larger size during the snowmelt, receding later to much tamer streams sustained by the constant drizzle and continuing snowmelt at higher elevations.  With little or no logging in the watershed, this water flows clear; the smaller streams (below) are partially choked with woody debris, which. like everything else here, decompose slowly.  As they decompose, these debris provide hiding places and nutrients for a number of organisms in the streams.  
Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

 

This being a group of aquatic biologists, it was no surprise that we spent a lot of time in the streams.  At the left, above, Steve Burian and Jordan Rosenfeld take samples from a stream.  Above, Steve, an old friend and mayfly expert, examines his catch.  These clean mountain streams yield a variety of aquatic insects, many of them adapted in one way or another to feed on the woody debris in the streams.

 

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Above you can see a close-up of some of the vegetation and the decaying logs that cover the ground.  The wood of many of the forest trees - Douglas Firs, Red Cedar and the like - are particularly resistant to insects and decay.  This makes them highly prized as lumber, and it also means that once these giants fall they will be a long time in decomposing.  

To the right, you can see clouds forming over the forests on the slopes of Mt. Lindemann overlooking Lake Chilliwack.

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

There were a number of epiphytes here, but overall there were not as many as you will see shortly in the images from the Hoh Rainforest.  The latter is more southerly, lower in elevation, and closer to the ocean, all conditions that conspire to make the Hoh a warmer temperate rainforest than you see at Chilliwack.,  Warmer means less snow; I've got to think that a lot of snow would tend to pull epiphytes off trees, and this may be one reason they are not as evident at Chilliwack.

 

The remainder of the pictures here from Chilliwack give you an idea of the wetlands and the forested mountain slopes that make up this majestic ecosystem.

 

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Chilliwack River Provincial Park, BC

Our hike took us from British Columbia, Canada, to the United States and back.  Here are 3 of the hikers standing somewhere in the US with Canada behind them.
Columbia River Gorge, Oregon

Columbia River Gorge, Oregon

A transition between the moist habitats along the coast and the dry habitats further inland.

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Our next field trip is to the Hoh River rainforest lying along the Hoh River on the Olympic Peninsula in Washington.  Average annual rainfall here is about 150 inches (380 cm).  Compared to the Chilliwack site, this is a warmer, lower rainforest; the pictures taken here were at about 600 feet in elevation; compare this to the 2,000 foot elevation of the Chilliwack area.  

Once again, water is one of the most noticeable features here, but, compared to Chilliwack epiphytes (above) are much more common.  To the left, a fallen tree creates a light gap.  These small patches of light are an important resource in the community; it is here that young trees get a chance to get started without being drowned in the shade of the larger trees.  

Below, more epiphytes hang from a tree at the left, and aquatic plants line the bottom of a small stream.

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

This small stream in the rainforest really caught my eye, particularly because of the bright green aquatic plants living in it.  You would expect a stream in a rainforest would be largely shaded, but there was enough light here for these plants to do extremely well.  There were several types of aquatic plants here, including a floating plant (below).
Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Above:  Epiphytes hung from virtually every surface in this rainforest.  Most of these are mosses and lichens, similar in many ways to the "Spanish Moss" of the southeastern United States, but this is only a superficial similarity.  The Spanish Moss is actually a type of bromeliad, while many of the epiphytes in the Hoh rainforest are actually club mosses.  For those of you with some botany, you will remember that club mosses are a very primitive type of plant, especially compared to bromeliads.    To the right and below you get a feel for the size of the trees here including huge Sitka Spruce. Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Above right a larger light gap is quickly filled with a variety of shrubs.  Above left, more epiphytes.  

The pictures left and below introduce the concept of nurse logs.  Nurse logs occur where seeds sprout and grow on fallen trees.  This is a distinct advantage to the seedlings, as they are held above the forest floor and the intense competition for light and nutrients that occurs there.  The decaying wood provides the initial "soil" and nutrients fro the seedling, which over time sends its roots down to the actual soil below.  Because of the decay resistant nature of the wood of many of the rainforest trees, the nurse logs may remain in recognizable form for decades, long enough for the seedlings to become sizeable trees in their own right.  The 3 pictures here show various stages in the nurse log seedling relationship.

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

More on nurse logs.  The picture above shows two large trees with intertwining roots; the roots are descending from the nurse log to the ground.  The picture to the right, above, shows the pedestal root form that one sees in many of the rainforest trees.  Here, the tree's trunk seems to start several feet above the ground; what has happened here is that the nurse log has finally decayed and the tree now appears "suspended" where the nurse log once was.  To the right, the mossy "field" in the foreground is actually the top of a fallen log, now covered completely by mosses; it is from a substrate like this that seedlings will one day sprout converting the fallen log into a nurse log. In the background many of the plants are broadleaved  as opposed to coniferous. The photos below show pedestal roots as the nurse logs decay away.  Note that in some cases more than one tree will share the same nurse log.   Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Above right:  A huge tree, hundreds of feet long, lies on the ground forming a wall to one side of a hiking trail.  This will make one heck of a nurse log someday.  The remaining images show a number of trees, mostly big-leaved maples, covered with epiphytes.  This warmer temperate rainforest is not as solidly dominated by conifers as the colder, higher latitude and elevation Chilliwack site was.  In the west, elevation is key to understanding ecosystems.
Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Hoh River Rain Forest

Finally, a few pictures of the river draining this rainforest.  The watershed is mostly protected by its status as part of a national park (although parts of the lower watershed are outside the park and periodically logged).  After the major snowmelt in the spring the river runs cold and clear.  It is home to a variety of aquatic species, including this case-making caddisfly, shown in an underwater photograph (right). Hoh River Rain Forest

Hoh River Rain Forest

 

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