Crossing the Channel
Potato Harbor, Santa Cruz Island, Channel Islands National Park, California
Just a few dozen miles off the coast of Southern California lie the Channel Islands, eight motes of land jutting out of the sea a stone’s throw from the hustle and bustle of the Los Angeles metropolitan area. Of the eight islands, the only one with a significant human population is the tourist mecca of Santa Catalina, which draws over one million visitors per year. The remaining seven islands are sparsely populated and draw far fewer tourists. The four northernmost islands form an archipelago that is protected by Channel Islands National Park and the Nature Conservancy.
Back in March, we briefly visited the largest Channel Island: Santa Cruz. At 97 square miles in area, Santa Cruz is reached via ferry from Ventura or Oxnard. Our hour-long journey across the Santa Barbara Channel was choppy to say the least, but included close up views of Pacific white-sided dolphins and several majestic oil drilling platforms. Upon arrival, we were greeted by one of the most lush landscapes imaginable. Abnormally abundant winter rains had produced a tall, dense carpet of green grasses that blanketed the entire island. One of the resident rangers told us it was the greenest he had seen Santa Cruz in the seven years he’d worked there.
A trail winding through the lush spring grasses on Santa Cruz Island, Channel Islands National Park
Looking east from Santa Cruz toward Anacapa Island, Channel Islands National Park
Campsite on Santa Cruz Island, Channel Islands National Park. Landscape illuminated by a first quarter moon.
Given their relative geographic isolation, the Channel Islands are notable for their high concentration of endemic plant and animal species found nowhere else on Earth. They are also home to some of the earliest evidence of human habitation in the Americas. Archaeological and geological evidence suggests that humans inhabited Santa Rosa, just east of Santa Cruz, as far back as 13,000 years ago. At this time, sea levels were much lower due to the massive amounts of water locked up in glaciers and ice sheets farther north. As a result, the four northernmost islands (Anacapa, Santa Cruz, Santa Rosa, and San Miguel) were united into a “mega island” whose eastern edge was much closer to mainland California. This made it easier for plants and animals to reach the island, either by air (birds, plant seeds, etc.) or on floating rafts of debris (mammals, reptiles, etc.) Some species may have even been deliberately brought to the islands by humans.
As the most recent glaciation ended, sea levels began to rise, eventually splitting the mega-island into the smaller landmasses that exist today. Once isolated, the plant and animal populations that had established themselves on the islands, either organically or after being brought there by humans, began to evolve into species distinct from their mainland cousins. In some cases, distinct subspecies have evolved on individual islands in response to unique conditions.
For visitors to Santa Cruz, the most obvious example of this phenomenon is the ubiquitous Santa Cruz island fox (Urocyon littoralis var. santacruzae). Coming from the mainland where a sighting (especially a daytime sighting) of a fox is a rare treat, we were surprised to see one within minutes of getting off the ferry. The island fox is descended from and appears very similar to the common grey fox, but is much smaller. A fully grown island fox weighs just 4-5 pounds, and is similar in size to a large house cat. Often the lush spring grasses exceeded the foxes in height, making them challenging to spot! Nearly extinct in the early 1990s, a highly successful habitat restoration and captive breeding program has the species thriving today. We ended up seeing several dozen in our short visit to Santa Cruz. Other subspecies of the island fox exist on five of the other seven islands, each with slight differences evolved in response to local conditions.
An island fox lurking in the tall grass
An island fox on the trail to Smugglers Cove, likely hoping for a food handout.
With its pastoral landscape and unique wildlife, Santa Cruz feels a world away from metropolitan areas of Southern California. However, nightfall brought a stark reminder of just how close the islands are to the urban sprawl. Light pollution from Los Angeles, Oxnard, Ventura, Santa Barbara, and the numerous oil drilling platforms in the Santa Barbara Channel dominated the night sky from Santa Cruz.
Nighttime panorama from the cliffs above Scorpion Ranch on Santa Cruz Island. See annotated image below for a description of the different features.
Our return trip was delayed because the choppy seas prevented the ferry from reaching the anchorage on Santa Cruz on time, giving us a few extra hours to sit on the beach and enjoy the peace & quiet of the island. The winds died down enough for a smooth ride back across the channel where we even spotted a couple of migrating gray whales. Apparently I need more practice shooting photos from a moving platform, as the whale pics all turned out pretty blurry. Have another fox instead!
Rocks and (Musk)Rats of the Rockies
Textbook stream meanders along the Fall River, Rocky Mountain National Park, Colorado
A few weekends back I led my semester-ly geology field trip to Rocky Mountain National Park. Each time I end up finding new gems that I had previously overlooked, such as the spectacular stream meanders along the Fall River pictured above. One good flood and the stream will erode through the narrow strip of land separating the two meanders, leaving the bend in the middle of the photo high and dry. Places like this are a great opportunity for students to see in action a geologic process that every introductory geology instructor teaches in the classroom.
Despite many areas of the park still being covered in umpteen feet of snow, wildflowers are beginning to appear in the lower elevations around Estes Park:
Early blooming pasqueflower in Moraine Park, Rocky Mountain National Park, Colorado
Longs Peak shrouded in a late-season storm, Rocky Mountain National Park, Colorado
The biggest cause for excitement actually occurred after the field trip was over. I had intended to stick around in the park for a longer hike after setting the students free, but I quickly realized I had left my filled camelback on the kitchen counter. Lacking any sort of water carrying device, not wanting to shell out the cash to buy one, nor desiring to try to fashion one out of ungulate intestines, that plan was foiled. In lieu of a hike I headed for a short stroll around Lily Lake to try to get some pictures of the incoming storm enveloping Longs Peak.
While snapping the above photo, I was startled by what sounded like a cannonball being dropped into the lake behind behind me. My initial suspicion of hooligans launching boulders into the lake was discredited when I turned around and saw no one within half a mile. I made my way to the edge of the lake and remained motionless; after a few moments, this little guy appeared:
Beaver? Otter? Furry fish?
Lily Lake, Rocky Mountain National Park, Colorado
Noticing the presence of a nearby mass of chewed up sticks (above), I hastily assumed I was in the presence of a beaver. In short time, a second critter appeared and the pair began to tussle, albeit sadly behind a willow bush from my point of view. It soon became clear that these animals were more agile and less chunky and rotund than your typical beaver. Not being able to see them clearly with the naked eye, my next guess was river otter, which persisted until I got home and took a closer look at the pictures below. Otters would have a tough time leading their carnivorous lifestyles with only those gigantic incisors to work with. I was out of ideas (this is why I lead geology field trips, not wildlife watching trips…) , so I was forced to the internet where I learned that I had just seen my first muskrat.
Two combative muskrats in Lily Lake, Rocky Mountain National Park
Nice teeth!
Finally, on the way home, I made a quick stop at a rock shop in Estes Park that I’ve driven past dozens of times. I quickly discovered that knowledge of basic geological principles is not a prerequisite for owning a rock shop when I found a large bin of black limestone labeled:
{facepalm}
A Sheep, a Sheep! My Kingdom for a Sheep!
Two bighorn sheep ewes in Big Thompson Canyon, Colorado.
After some memorable elk encounters this past fall, I’ve been on the lookout for more wildlife viewing opportunities over the past few months. A flock of several thousand Canadian geese passing overhead while extricating my car from a foot of snow at the Denver airport didn’t quite cut it so on a recent weekend, we headed out in search of one of Colorado’s most iconic creatures: the Rocky Mountain Bighorn Sheep.
It turns out that late November and early December is the best time of year to view Rocky Mountain Bighorn Sheep here in the foothills of the Colorado Rockies. This time period marks the annual bighorn sheep rut, or mating period. While the bighorn sheep rut attracts far less attention than the fall elk rut, at this time the sheep descend from higher elevations to avoid deep snowpack and are frequently seen along canyons such as the Big Thompson, just a short half hour drive from Fort Collins (where I now live).
If that name sounds familiar, it’s because Big Thompson Canyon is better known as the site of a number of large and particularly deadly floods in the past few decades than as prime bighorn territory. But in late autumn and early winter, this is the place to be for some serious sheep spotting and shooting (with a camera of course!). This is not to say the sheep are always easy to spot. The beige bighorns, with the exception of their white butts, blend into the brown and shrubby landscape extraordinarily well. Here’s a view of the second pack of sheep we spotted to better illustrate the challenge:
Find the FOUR bighorns!
You can see the problem: brown vegetation + brown rocks + (mostly) brown sheep = hard to spot sheep. It’s like Where’s Waldo, only in real life and with sheep instead of fictional characters with questionable fashion sense. Anyways, when whizzing by at 50 mph (the minimum speed required to avoid being rear-ended by folks hellbent on getting to Estes Park) on a road with little to no shoulder, it helps to have at least one pair of eyes apart from the driver to scan the cliffs and ledges so loved by the sheep for movement or a flash of a white rump.
In the end we spotted two groups of bighorns in about two hours in the late morning, the first group containing one ram and three ewes, the second two rams and three ewes. The first group was bedded down right along the Big Thompson River, just a stone’s throw from the highway right at the entrance to the canyon. With a little creative parking and scrambling, I was able to get some good close-ups of the sheep (see top photo and below). The second group was larger and more active, but was in a gully across the river over a hundred yards from the road, well outside the range of my pathetic telephoto equipment.
The presence of two rams in the second group was exciting because it afforded the possibility of seeing the famous bighorn sheep head-butting combat ritual in action. Alas though, these rams seemed much more interested in quietly grazing on the scant remaining greenery than in slamming their heads together at speeds of more than 30 mph (who wouldn’t?)
A good look at the large curved horns on the male bighorns, used in head-butting competitions with other males for the right to mate with prime females.
The bighorn sheep will continue to be visible in the Big Thompson area throughout the winter (as they avoid the deep snowpack at higher elevations) although once the rut concludes they become much more averse to human contact and populated areas. Unlike some other notable large mammals of the Rockies, bighorn sheep tend to be most active during daytime hours, making them relatively easy to spot if you have a keen eye.
