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Posts Tagged ‘Behavior’

Homosexuality has been observed is just about every species it has been looked for. Transgender animals are not as widely known, but may just be a matter of looking for them.

There are certainly some animal examples that are various forms of transgender animals in nature. One is the California Sheephead (Semicossyphus pulcher) which is a fish that is born female, and then can become male later in life. Another example is found in the Green Frog (Rana clamitans) that reverse sex in response to various external factors, and this has been observed in other amphibians as well. But both of these examples are in lineages of animals that are pretty distantly related to us humans.

lionesses-with-manes

Photo of two lions one is male sex (left), one is female sex (right), but both display male characteristics.

Well, research published a couple of years ago in the African Journal of Ecology is an example much closer to us. In a paper by Gilfillan et al. from the University of Sussex, five lionesses in Botswana have been observed to grow manes, regularly roar and scent mark, mount other females, and display other very male-like behaviors such as killing the cubs of rival prides which females lions just about never do but is very common for male lions.

This is a mammal we are talking about.

Lions that are female in body, but male in behavior.

In the wild.

Still think being transgender is unnatural?

Transgender Flag

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My wife, daughter and I were in Berkeley, CA this weekend visiting my mom and some friends. One morning, while we were having breakfast and watching the visitor to the bird feeders hanging not far from the floor-to-ceiling windows, we witnessed a pretty dramatic event.

PUFI

A female or juvenile Purple Finch.

As we eat our breakfast, a group of three or four Purple Finches were enjoying their’s. Suddenly, a California Scrub-Jay made an ambush attach on the feeder! It flew in through the branches of the Incense Cedar, and startled the finches into a bit of a panic. One of the Purple Finches (either a female of juvenile bird) made a very bad decision, and flew directly away from the incoming jay which meant it crashed into the big windows right in front of us. The jay flew past the feeder, not stopping at all, and landed on a table near the big windows. It seemed from watching the flight of the jay, that landing on the table had been its plan. The finch was on the deck, stunned by the impact with the window. The jay looked down, watched the finch for a moment to assess its condition, and then jumped down, grabbed the adult finch in its beak and flew away toward a large tree that we are pretty sure this bird and its mate have a nest in! That’s right, as if it was pretending to be one of the small hawks or falcons, the jay picked up the stunned Purple Finch and flew off with it!

CASJ

California Scrub-Jay

This whole event only took a total of about one minute, but it got us all talking and thinking a fair bit about what we had just seen. First off, What a sight to see! All of us around our breakfast table were pretty surprised, impressed, and a few were taken aback at seeing a predator prey interaction at such close range. Secondly, I have never seen a California Scrub Jay prey on an adult songbird, before! I looked it up, and while there are reports of similar behaviors, they are not common. Thirdly, was driving a finch into the window the jay’s plan? The jay seemed like it was aware of the window, as its movements never put it in any danger of colliding itself. The finch was either unaware of the window, or was so frightened by the jay’s sudden attack that it forgot about it. So, did the jay basically hunt the Purple Finch using a window? Jays, members of the corvid family along with ravens, crows, magpies, and others, are highly intelligent and have been observed using tools in a range of settings. So, using a tool such as a known window location to incapacitate prey certainly seems possible.

Regardless of whether or not the window was used as a hunting tool, or if the jay just got lucky, this was a pretty impressive sight to see. And those baby jays had a very big breakfast of their own that morning!

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A post from AbirdingNaturalist has been accepted to the website NatureWriting! With the acceptance of my piece titled “A Vomiting Vulture,” I am now a contributor. This is the first time one of my posts has been featured on another website, so I am pretty excited!

NatureWriting can be found here.

My post can be found here.

Check them out!

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OR_25 May 20 2014_Imnaha PackAllow me to introduce you to OR-25, the most recent wolf visitor to the great state of California. This very handsome 3-year-old fellow recently left his Imnaha Pack in eastern Oregon. He decided to walk south and, just last week, crossed into California where he has been hanging out in Modoc County. His arrival, along with OR-7 who visited for most of 2012 before settling just north of the California/Oregon border to have babies and the Shasta Pack that has established itself in Siskiyou County in 2015, may indicate that wolves are starting a trend of dispersal and range expansion into this state. If this expansion continues, we who live in California may be lucky enough to encounter these long-lost members of our state’s wilderness. I am certainly hoping for it!

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As part of my current job with the California Department of Water Resources, I assist in collecting data for a study that is monitoring predators in the Clifton Court Forebay (CCF). The CCF is where water is collected and then pumped into the California Aqueduct for transport to southern California. One of the challenges to providing water to southern California is that there are several threatened or endangered species that live in the delta. Fish that get sucked into the pumps of the aqueduct do not survive, so keeping state and federally list species out of the system is important. The study I have been working on the past four months is examining threats to the listed species. One component of that study is to catch predatory fish such as Stripped Bass (Morone saxatilis), Largemouth Bass (Micropterus salmoides), and several species of Catfish (Ictalurus spp. or Ameiurus spp.). Once captured, these fish are tagged with little transmitters that send out signals that can be detected by underwater microphones, called hydrophones, that are setup throughout the area. By tracking when and where these predatory fish go, we hope to be able to figure out a way to reduce the number that come into CCF and eat the listed species.

Fall-run Chinook Salmon

Fall-run Chinook Salmon

One of the listed species we are concerned with are Chinook Salmon (Oncorhynchus tshawytscha), and I got an up close and personal look at one just a few days ago. As the team I was a part of was fishing in CCF, I got a hit on the lure I was using. It felt like a brick had been dropped on my line as the fish swam away from me and the boat. As I worked to real the fish in, everyone on the boat was getting curious to see what species I had hooked, just how big it was going to end up being. When I had finally pulled the fish to the surface, we were all really surprised to see that it was a Chinook! We are not supposed to catch salmon, and generally they do not attack the lures we use, additionally salmon at this time of year are not really eating but are instead focused on finding a mate and spawning. So this really was a surprise! When we got it on board to get the hook out of its mouth we quickly measured it (61 cm), weighted it (6.55 lbs), and got it back in the water so that it could go on its way.

Getting to see this fish, the largest fish I have ever caught, to hold it and then to watch it return to the water got me thinking a lot about Chinook Salmon. I am starting a new job on Monday which will focus on restoring many areas of the delta, and listed species will be a large part of those projects, so I figured that learning a bit more about salmon would be a good idea.

It turns out that there are four different runs of salmon that move through the California Delta. The different runs are defined according to when the different populations enter freshwater as they travel up from the Ocean and San Francisco Bay through the Delta and up the various rivers of California. The four runs are the Central Valley Fall-run, the Central Valley Late Fall-run, the Sacramento River Winter-run, and the Central Valley Spring-run. Each of these runs are considered to be evolutionarily significant units and so are monitored and managed for their specific needs.

Central Valley Fall-run Chinook, like the one I caught, are the most abundant of the four runs. They move through the area from July to December and spawn from early October through December. There is a fair bit of variability from stream to stream. Fall-run Chinook are an important economic factor due to the large numbers that are caught by both commercial and recreational fisheries in the ocean and by recreational anglers  once they reach freshwater. Even so, due to concerns about population size and the influence of hatchery-raised Chinook, this run is listed as a species of concern under the federal endangered species act.

Central Valley Late Fall-run Chinook migrate into the river systems from mid-October through December and spawn from January through mid-April. Again, due to concerns about population size and the influence of hatchery-raised Chinook, this run is listed as a species of concern under the federal endangered species act.

Sacramento River Winter-run Chinook pass through the Golden Gate from November through May and then move into the Sacramento River from December all the way through early August. They then swim up the mainstem of the Sacramento River to spawn from mid-April through August. These salmon used to go farther up the Sacramento River watershed and spawn in the McCloud River, the Pit River, and the Little Sacramento River. However, the construction of several dams have not blocked access to these historical spawning grounds. Despite these dams, the population of Sacramento River Winter-run Chinook was able to maintain a fairly healthy level until the 1970s when they began to decline. By the early 1990s only about 200 spawning salmon were observed. In 1989 this run was listed as endangered under the California Endangered Species Act and they were then listed as endangered under the federal Endangered Species Act in 1994.

Central Valley Spring-run Chinook begin moving up the Sacramento River from March through September. They generally the find areas of cold water to wait out the summer and then spawn from mid-August through October. This run used to be the largest in central California however, only small remnant populations are left in small creeks that make up some of the tributaries of the Sacramento River. Some Spring-run Chinook still occur in the mainstem of the Sacramento and Feather Rivers, but they sometimes hybridize with Fall-run Chinook. The reduced spawning areas, small population size, and hybridization threat lead the Central Valley Spring-run Chinook to be listed as threatened under both the federal and California Endangered Species Acts in 1999.

So, there you have them, the four Chinook Salmon runs of the California Delta. There are many other runs in other parts of the state, all with their own unique stories and histories. It will be interesting to see how I will be interacting with these runs in the habitat restoration work I will be doing. I will keep you informed!

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Early March is a wonderful time in the central valley of California. It is becoming warmer, although this year it never really got that cold. A few rain showers bring welcome and much needed moisture to a region entering its fourth year of drought. The calla lilies are blooming and the first jasmine blossoms give the air the faintest hint of their wonderful, soft fragrance, a fragrance that will become much stronger over the course of the month. A few days ago, I saw my first Swainson’s Hawk of the year. These birds are just returning to the area after flying from as far a way as Argentina, and will be setting up their territories soon. Another first of spring that occurred a few days ago was my first Valley Carpenter Bee. It was a beautiful black female flying from flower to flower. Soon there will be lots of these large friendly bees zooming around. As my two-year-old daughter and I play in our front yard, yesterday, we watch a pair of Bushtits searching through one of the oaks that line the edge of the lawn. A pair of Bushtits (the same birds?) have built their hanging pendulum of a nest and raised a clutch of babies in this same oak tree for the past two years. Will this be year number three? Laying on the lawn, we find the remains of last year’s nest which has only now fallen from where it hung. The long sock-like construction of moss and lichen and feathers all held together by spider silk is soft to the touch and impressively flexible and elastic! We also see American Crows starting work on their nest. The pair, and a few helpers, have chosen to nest near the top of one of the redwood tress in a neighbor’s yard. Some crows (again, maybe the same ones?) nested in this same tree two years. Last year they moved about 100 meters away and nested in a pine, but now they are back to their redwood tucking sticks together just a few feet from the top of the tree. While this breeding activity is ramping up, there are still many winter birds readying themselves for their vernal migration away from the central valley. Ruby-crowned Kinglets and Yellow-rumped Warblers call as they forage in the trees finding insects and building up energy reserves for the trip to the breeding grounds and the marathon that is a birds breeding season. Cedar Waxwings are also still around in fairly high numbers. Recently, there have been so many in the sycamore trees right outside our door that their high-pitched calling becomes a constant background noise behind any other activity. So much to watch and enjoy. I hope early March where you are is just as fascinating and enriching.

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Last week, on my birthday, I went out to bird along the Clarksberg Branchline Trail in West Sacramento, Ca. I was out on the trail at 6:30 just before dawn and wandered around for about an hour. The section of the trail that I was birding is really close to my condo and as such is a spot that I bird pretty frequently. This morning was one of those mornings that reminded me of why it so special, and important, to get out to places close to where you live and see what is happening in the world.

It was a great morning of birding. I saw a Red-breasted Sapsucker searching for food high in a oak, found many Varied Thrushes foraging in the leaf litter for insects and worms, watched a pair of Red-shouldered Hawks as they flew screaming across an open field straight towards me to land in a tree right over my head, and found a White-throated Sparrow (an unusual winter visitor to the west coast and my favorite member of the genus Zonotrichia) hanging out with a group of Golden-crowned Sparrows! The birds were wonderful, and I was right around the corner from my house, and only there for an hour! You do not need to work hard for great birding.

These small, local birding explorations are not grand adventures. They are not exhilarating chases to see some incredibly rare species. They do not generally produce stupendously high species totals. But what they are is the bread and butter of birding experiences. They keep us in touch with the movements and pulses of the natural world right around where we live. Pulses that can go unnoticed all too easily in our modern busy lives. These local explorations give us the one-the-ground knowledge of what creatures are living next door, of how the environment changes from season to season and year to year, of exactly where a given bird can be found and what they like in a habitat. This is not knowledge that can be obtained easily, and it is knowledge that can be of great import. So get out to visit the local spots that are close to you and keep an eye on what is going on. you never know what you are going to find!

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