Archive for June, 2012

As my wife and I were driving from our apartment to downtown Davis, today, we watched two adult, light-morph Swainson’s Hawks diving and chasing each other over I-80.  They were not acting especially aggressively towards each other, but rather were flying after one another in a more playful manner.  At one point, in the midst of their swooping and diving, they both gained a fair bit of altitude, flew straight toward each other, and locked talons!  They began to fall and spin directly toward the streaming highway traffic below.  For a brief moment, I thought I was about to witness a tragic crash, but then separated well before they actually got down to car and truck level.

I have only rarely seen this talon grappling behavior before, and never done by a pair of Swainson’s Hawks.  It was very dramatic!  This is usually done by birds of prey during the courtship period when two birds are setting up a territory and settling on each other to have babies with this year.  Late June is not when this kind of thing would be expected seeing as most all the birds are now in the hatching eggs stage of the breeding season.  However, just like humans, raptor pairs occasionally take a few moments out of their busy days to spend some quality time with each other.  This time serves to reenforce and strengthen their pair-bond, and may contribute to higher rates of nest success.

So, take a few moments, find your sweetheart, and reenforce your pair bond…and by that I mean that you should lock talons together and spin a little!

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We have two bird feeders hanging above the little patio of our apartment, and the most regular species that we have as visitors are House Finches.  We have them all year round with large numbers in spring and fall as the waves of migrants move through central California, a smaller number that stays through winter, and just a handful of birds regularly come to the feeders during the summer breeding season.  I strongly suspect that this is because the House Finches space their breeding territories out to where only two or three are close enough to allow the birds access to the feeders without them having to cross into a neighbors territory too much.

Yesterday morning one of the pairs was accompanied for the first time by two fledglings!  These young birds were capable of a decent amount of flight, thought they were still doing so somewhat clumsily, but they are completely reliant on their parents for food.  Each of the two fledglings picked one of the parents and followed that adult around from fence top to ground and back again begging for food all the while. The parents are more then skilled enough to fly up and land on the feeders, but the young ones do not yet have the skills.  Instead, the young birds simply give their begging calls and tremble their wings in the hope that this behavior will trigger the adult they are following around to turn and feed them.  The adults spent most of their time picking seeds off the ground and, when they had gathered a crop full, feeding the fledgling trailing behind them.  The fledglings watched the adults picking seeds off the ground with obvious interest, but little understanding.  The second most common bird at our feeders are Western Scrub Jays.  We have one pair of Jays that have claimed out feeders and let no other Jays come anywhere close to them.  This pair built a nest in a Cottonwood tree just across the parking lot from out patio.  It is about 20 ft above the ground on a branch that is particularly dense with foliage.  Today, when they came to the feeders, they were accompanied for the first time by one fledgling of their own!  This young bird also has the occasional tuft of down still poking out through its course Juvenal feathers.  The young Jay also seems to have about the same level of understanding of the world as the young House Finches seem to.  It follows its parents and begs for food.  It watches the adults gather seeds and break them open with apparent curiosity, but does not have any understanding of how to go about actually performing this task.  Instead, it follows its parents and begs for food with fluttering wings.

It will take a little while for any of these fledglings to figure out that those hard black things are sunflower seeds and that there is food inside them.  It will take them all even a bit longer to figure out how to actually open the shell.  A very fun process to watch.

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Songs and Calls

The vocalizations of birds can be divided into two broad categories: songs and calls (Catchpole and Slater 1995).  Songs tend to be complex, usually multisyllabic, often musical, and are generally learned by young individuals from adults that they hear and imitate.  They are used in territory establishment and defense, mate attraction, and to discourage potential rivals.  Calls tend to be structurally simpler, often monosyllabic, and have historically been thought to develop innately.  Calls are given in a wide range of contexts, but most calls can be placed into one of several categories: alarm call, contact call, roosting call, food call, begging call, or agonistic call (Marler 2004).  With the wide range of information that can be transmitted, studies of calls have taught us a great deal about communication and social structure in avian populations.  However, calls have historically been the focus of much less intense study than songs, and there is much that remains to be learned.  The diversity in repertoire, the levels of species specificity in particular calls and how this level changes with the category of call and the context in which it is given, and the selective pressures on both the call sender and receiver are all areas that warrant further and more detailed investigation.

Functions and Structure of Different Calls

Alarm Calls – Alarm calls can be divided into three subcategories – flee alarm, assembly alarm, and alert calls; calls in these subcategories tend to elicit different responses (Bradbury and Vehrencamp 1998).  The flee alarm is a signal sent to nearby individuals and tends to cause receivers to move rapidly away from the sender and/or to seek cover.  In many species, this signal can vary depending on the type of threat detected (aerial predator vs. terrestrial predator for example) and also on the proximity of the predator (Leavesley and Magrath 2005).  White-browed Scrubwrens (Sericornis frontalis) have been shown to increase the number of elements in their flee call with proximity of a suddenly appearing predator, and flee calls with larger numbers of elements also prompted more urgent responses in receivers (Leavesley and Magrath 2005).  Distress calls are an extreme form of flee alarm usually only given when an individual finds itself severely threatened.  These calls are loud, usually include a harsh rasping or screaming quality, and are often repeated rapidly.  Some evidence suggests that birds may give a distress call, when it is being attacked by a predator, to attract other predators with the result being that the new predator will compete with, and possibly drive off the current predator and so allow the prey to escape in the confusion (Koenig et al. 1991).  In some species the distress call attracts other members of the same species, and sometimes members of other species as well, that may then attempt to drive off the predator (Chu 2001, pers. obs.).

The assembly alarm (often calls a “mobbing call”, Bradbury and Vehrencamp 1998) is typically produced when a predator is located, causing receivers that are more widely dispersed to move toward the sender.  The information that is conveyed by these calls can not only include the location of the sender, but the location and type of threat as well.  This was demonstrated by Templeton et al. (2005), where presentation experiments revealed that Black-capped Chickadees (Poecile atricapilla) varied their mobbing calls, and their responses to these calls, in response to predator body size.

Calls that fall somewhere between the extremes of flee alarms and assembly alarms are alert calls.  These signals do not tend to cause receivers to move.  They are hypothesizes to inform other individuals of possible threats or other changes in the local environment (Seyfarth et al. 1980).  They may also be used to tell predators that they have been detected causing the predator to hunt other, less vigilant, prey (Caro 1995).  Studies suggest that when a local prey population has been alerted to the presents of a predator, the predator is less likely to succeed in its attempts to capture prey (Bergstrom and Lachmann 2001, Zuberbühler et al. 2009).

Each of these categories of alarm call can contain multiple distinct vocalizations.  Heterospecifics may also perceive and respond to these calls (Hurd 1996, Nolan and Lucas 2009).  For different species to correctly interpret a signal, that signal must have certain characteristics that cause it to be recognized by a wide and varying group.  Such characteristics may include relatively low variability and/or acoustic characteristics that are common to many species.  An example of common characteristics is given by Jurisevic and Sanderson (1994) who found that of the 30 species of bird examined, representing a wide range of taxa, 29 of them produced an alarm call with broad frequency range and a noisy or harmonic structure.  These calls do differ in area of active space, the area over which a call can be detected (Brenowitz 1982).  Flee calls are sent when danger is immediate and received by individuals that are close by (Magrath et al 2007).  Both of these conditions encourage the sender to vocalize relatively quietly and so improve the odds of the sender avoiding detection.  Distress calls are an exception to this in that they are loud, harsh sounds that may cause a predator to startle and stop the attack (Laiolo et al 2004, pers. obs.).  Assembly calls, contrastingly, attract individuals from some distance away, and so need to be louder than standard flee calls (Johnson et al 2003).  They must easily localizable using binaural cues or provide information about the location of the sender in order to effectively elicit a mob (Templeton et al. 2005).

Contact Calls – Contact calls are used by individuals of both sexes throughout the year and are thought to facilitate group cohesion, keeping group members in acoustic and/or visual contact.  They have a wide range of variation depending on the distance between the individual and the rest of the group and also depending on who is separated from whom.  They can be unique to individuals, allowing specific communication between particular individuals (Dooling et al. 1992, Bradbury 2003).  Contact calls may provide information to receivers about the approximate distance and activity level of the sender (Dooling et al. 1992).  The sound characteristics of, and response to, these calls are generally species specific (Wanker and Fischer 2001, Sharp and Hatchwell 2005).

Flight calls are a special form of contact call.  These calls are given while a flock is preparing to take flight and also during flights, and are hypothesizes to signal and coordinate group movements.  Flight calls are given by both sexes throughout the year, but are usually much louder than most other contact calls.  They can also be used to identify group membership and individual identity.  Mundinger (1970) found that female American Goldfinches (Carduelis tristis) could discriminate between the flight calls of their mate and those of other males.  Balsby and Bradbury (2009) found that Orange-fronted Conures (Aratinga canicularis) used their ‘chee’ call when two flocks were approaching one another to orchestrate flock fission or fusion.

Individual discrimination requires that a particular bird gives their own variant of a call with consistency in at least some acoustic features so as not to be confused with other individuals (Berg et al. 2010).  It also necessitates a wide range in variation across the whole population to allow for so many discrete variant to exist in acoustic space (Wanker and Fischer 2001).

Roosting Calls – Many species of bird vocalize as they are settling into night roosts.  Some tend to be sent over short distances such as a female calling her young to where she has settled for the night (Collias and Joos 1953).  Others tend to be sent over larger distances such as in a large flock of birds, like those observed in blackbirds or crows which gather together in the evening at a roost site (Hill and Lein 1985).  It is thought that members of these large flocks can gain information about local resources by how the flock breaks up each morning (Ward and Zahavi 1973, Buckley 1996, Dall 2002).  In this way, roosting calls serve as a way for individuals to locate flocks and so be in a position to benefit from the flocks’ collective knowledge the next morning.

Food Calls – Food calls are produced when the sender locates a food source (Elgar 1986, Buitron and Nuechterlein 1993), and may function to advertise a food find to receivers.  Senders may benefit for producing these calls, since receivers are typically young or close relatives of the sender, or potential mates (Buitron and Nuechterlein 1993).  For example, male domestic chickens are more likely to give food calls when there is another chicken nearby than when they are alone (Evans and Marler 1994), indicating that the calls have a communication function and are not simply a response to food.  Food calls are also more common when the nearby chicken is female which indicates the use of food calls in courtship (Marler et al 1991).  Some males have been observed to give food calls when holding a non-food item such as a stick, but only when the female is some distance away.  These males seem to be attempting to deceive the female with a false attractant which can only be detected as such with close proximity (Gyger and Marler 1988).    For food calls to be effective, therefore, the sender must be locatable and must be identifiable to individual; locatable so that the other birds can determine where the food source is, and identifiable to individual so that they can possibly assess the trustworthiness of the sender (Gyger and Marler 1988).  Birds outside of Galliformes rarely produce food calls and when they do occur it is usually around an extremely abundant food source (Elgar 1986, Heinrich 1989, Brown et al. 1991, Mahurin and Freeberg 2009).

Begging Calls – Begging calls are given most commonly by young to adults to elicit feeding (Godfrey 1991).  To be effective, adults must be able to locate and identify their own young.  In solitarily nesting species adults do discriminate between individual nestlings (Redondo and De Reyna 1988), but they have no need of discriminating between their own young and those of a different adult because when they return to the area of their nest, their own young are the only young present.  However, in colony nesting species, the task for an adult to correctly identify its own offspring out of a group of nests or young birds becomes much more challenging.  Beecher (1989, 1990) showed that individual nestling Barn Swallows (Hirundo rustica), which nest apart from one another, have much less stereotypy in their begging calls than do nestling Bank Swallows (Riparia riparia), which nest colonially.  Beecher argued that each Bank Swallow nestling must produce its own particular begging call variation very consistently so as not to overlap with its neighbors.  However, as a whole, a Bank Swallow colony will have many more begging call variants than a comparable number of solitarily nesting Barn Swallows, which can have overlapping begging call from nest to nest.  These studies serve to illustrate how the amount of variation, in terms of acoustic properties of a call in acoustic space, within an individual is related to how close the nearest neighbor is in terms of the same acoustic space.  Birds that have many other individuals close by must be very specific in the calls they give to avoid being confused with their neighbors, whereas bird that has no close neighbors is not so constrained.

Agonistic Calls – Aggressive behavioral interactions frequently include vocalizations, referred to as agonistic calls.  These calls can be given at any time of year, and are typically used to drive off, or decide the fighting ability and/or vigor of, the receiver.  Receivers can be other individuals of the same species, other species of bird, or even non-avian intruders.  These calls are usually harsh sounds and have a fairly large degree of variability, are usually given at close range, and do not contain information on the location of the sender (Black and Owen 2004).

Cited Literature

Balsby, T.J.S. and Bradbury, J.W., 2009. Vocal matching by orange-fronted conures (Aratingacanicularis). Behavioral Processes 82, 133-139.

Beecher, M.D., 1989. Signaling systems for individual recognition: An information theory approach. Animal Behavior 38, 248-261.

Beecher, M.D., 1990. “The evolution of parent-offspring recognition in swallows.”  In: Contemporary Issues in Comparative Psychology. Dewsbury, D. Sinauer Associates, Sunderland, MA.

Berg, K.S., Delgado, S., Okawa, R., Beissinger, S.R., and Bradbury, J.W. 2010. Contact calls are used for individual mate recognition in free-ranging green-rumped parrotlets, Forpus passerinus. Animal Behaviour 81, 241-248.

Bergstrom, C.T. and Lachmann, M. 2001. Alarm calls as costly signals of antipredator vigilance: the watchful babbler game. Animal Behaviour 61, 55-543.

Black, J.M. and Owen, M. 2004. Agonistic behavior in barnacle goose flocks: assessment, investment and reproductive success. Animal Behaviour 37, 199-209.

Bradbury, J.W. 2003. “Vocal communication in wild parrots.” In: Animal Social Complexity: Intelligence, Culture and Individualized Societies. DeWaal, F.B.M. and Tyack, P.L. Harvard University Press, Cambridge, MA.

Bradbury, J.W. and Vehrencamp, S.L. 1998. Principales of animal communication. Sinauer Associates, Sunderland, MA.

Brenowitz, E.A. 1982. The active space of red-winged blackbird song. Journal of Comparative Physiology 147, 511-522.

Brown, C.R., Brown, M.B., and Shaffer, M.L. 1991. Food-sharing signals among socially foraging cliff swallows. Animal Behaviour 42, 551-564.

Buckley, N.J. 1996. Food finding and the influence of information, local enhancement, and communal roosting on foraging success of North American vultures. Auk 113, 473-488.

Buitron, D. and Nuechterlein, G.L. 1993. Parent-young vocal communication in eared grebes. Behaviour 127, 1-20.

Caro, T.M. 1995. Pursuit-deterrence revisited. Trends in Ecology and Evolution 10, 500-503.

Catchpole, C.K. and Slater, P.J.B. 1995.Bird song: biological themes and variations. Cambridge University Press, Cambridge, MA.

Chu, M. 2001. Heterospecific responces to scream calls and vocal mimicry by phainopepla (Phainopeplanitens) in distress. Behaviour 138,775-787.

Collias, N.E. and Joos, M. 1953. The spectrographic analysis of sound signals of the domestic fowl. Behaviour 5, 175-188.

Dall, S.R.X. 2002. Can information sharing explain recruitment to food from communal roosts? Behavioral Ecology 13, 42-51.

Dooling, R.J., Brown, S.D., Klump, G.M., and Okanoya, K. 1992. Auditory perception of conspecific and heterospecific vocalizations in birds: evidence for special processes. Journal of Comparative Psychology 106, 20-28.

Elgar, M.A. 1986. House sparrows establish foraging flocks by giving chirrup calls in the resource is divisible. Animal Behaviour 34, 169-174.

Evans, C.S. and Marler, P. 1994. Food calling and audience effect in male chickens, Gallus gallus: their relationships to food availability, courtship and social facilitation. Animal Behaviour 47, 1159-1170.

Godfrey, H.C.J. 1991. Signaling of need by offspring to their parents. Nature 352, 328-330.

Gyger, M. and Marler, P. 1988. Food calling in the domestic fowl, Gallus gallus: the role of external referents and deception. Animal Behaviour 36, 358-365.

Heinrich, B. 1989.Ravens in Winter. Simon and Schuster, NY.

Hill, B.G. and Lein, M.R. 1985. The non-song vocal repertoire of the white-crowned sparrow. Condor 87, 327-335.

Hurd, C.R. 1996. Interspecific attraction to the mobbing calls of black-capped chickadees (Parusatricapillus). Behavioral Ecology and Sociobiology 38, 287-292.

Johnson, F.R., McNaughton, E.J., Shelley, C.D., and Blumstein, D.T. 2003. Mechanisms of heterospecific recognition in avian mobbing calls. Australian Journal of Zoology 51, 577-585.

Jurisevic, M.A. and Sanderson, K.J. 1994. Alarm vocalizations in Australian birds: convergent characteristics and phylogenetic differences. Emu 94, 69-77.

Koenig, W.D., Stanback, M.T., Hooge, P.N., and Mumme, R.L. 1991. Distress calls in the acorn woodpecker. Condor 93, 637-643.

Laiolo, P., Tella, J.L., Carrete, M., Serrano, D., and Lopez, G. 2004. Distress calls may honestly signal bird quality to predators. Proc. R. Soc. Lond. B (Suppl.) 271,S513-S515.

Leavesley, A.J. and Magrath, R.D. 2005.Communicating about danger: urgency alarm calling in a bird. Animal Behaviour 70, 365-373.

Magrath, R.D., Pitcher, B.J., and Gardner, J.L. 2007. A mutual understanding? Interspecific responses by birds to each other’s aerial alarm calls. Behavioral Ecology 18, 944-951.

Mahurin, E.J. and Freeberg, T.M. 2009. Chick-a-dee call variation in Carolina chickadees and recruiting flockmates to food. Behavioral Ecology 20, 111-116.

Marlar, P. 2004.“Bird calls: a cornucopia for communication.” In: Nature’s Music: the science of birdsong. P. Marler and H. Slabbekoorn, Elsevier Academic Press, New York, NY.

Marler, P., Karakashian, S. and Gyger, M. 1991. “Do animals have the option of withholding signals when communication is inappropriate? The audience effect.” In: Cognitive Ethology: The Minds of Other Animals. C. Ristau, Lawrence Erlbaum, Hillsdale, NJ.

Mundinger, P.C., 1970. Vocal imitation and individual recognition of finch calls. Science 168, 480-482.

Nolan, M.T. and Lucas, J.R. 2009. Asymmetries in mobbing behaviors and correlated intensity during predator mobbing by nuthatches, chickadees and titmice. Animal Behaviour 77, 1137-1146.

Redondo, T. and De Reyna, L.A. 1988.Locatability of begging calls in nestling altricial birds. Animal Behaviour 36, 653-661.

Seyfarth, R.M., Cheney, D.L., and Marler, P. 1980. Monkey responses to three different alarm calls: evidence of predator classification and semantic communication. Science 210, 801-803.

Sharp, S.P. and Hatchwell, B.J. 2005. Individuality in the contact calls of cooperatively breeding long-tailed tits (Aegithalos caudatus). Behaviour 142, 1559-1575.

Templeton, C.N., Greene, E., and Davis, K. 2005. Allometry of alarm calls: black-capped chickadees encode information about predator size. Science 308, 1934-1937.

Wanker, R., and Fischer, J. 2001. Intra- and interindividual variation in the contact calls of spectacled parrotlets (Forpus conspicillatus). Behaviour 138, 709-726.

Ward, P. and Zahavi, A. 1973. The importance of certain assemblages of birds as “information-centers” for food-finding. Ibis 115, 517-534.

Zuberbühler, K., Jenny, D., and Bshary, R. 2009. The predator deterrence function of primate alarm calls. Ethology 105, 477-490.

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I went for a walk along Putah Creek yesterday at the South Fork Preserve.  The early morning was windy and not yet hot, but the sky was clear and the sun was bright.  When I got to the first creek access point, I was treated to a view downstream of the creek scattered with egrets and herons (all members of the family Ciconiiformes).  Usually there are one or two, but I have never seen this many along the creek before.  About half-a-dozen Black-crowned Night Herons were perched in some dead and fallen branches just above the water line.  Three Snowy Egrets were just beyond them foraging in the shallows skittering their feet around in the mud and silt and darting off after food when it was disturbed by the egret’s agitated foot movements.  A bit farther into the channel, stood 5 Great Egrets.  They were all hunting through an area of the creek that was thick with aquatic plants and alga.  They stood almost motionless, waiting for some unsuspecting prey to swim by.  Out in the deeper water in the center of the channel were the 3 Great Blue Herons using the same hunting strategy as the Great Egrets, they stood waiting.

Watching these birds all crowded into the same area got me thinking on how each species utilizes a different part of the habitat and has characteristic behavioral differences that help then to do so, a concept known as niche partitioning.  But which came first, the different species or the different behaviors?  Perhaps populations of ancestral Ciconiiforms became somehow reproductively isolated and so became different species, and then these different species developed different behaviors.  Alternatively, perhaps different behaviors arose in that ancestral species that allowed some members to use one part of the habitat better, and other members use a different part of the habitat better, and this then led to assortative mating and speciation.  And the answer is not necessarily the same for all species, in fact it is almost certainly not.  But how often does reproductive isolation come first?  How often is behavioral differentiation the inciting incident?  No one is really sure, but I find it fascinating to think about.  Gaining a greater understanding of how these different processes work and interact will give us a greater understanding of evolution and natural selection as a whole.

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A friend sent me this video.  The huge flock of European Starlings is truly amazing, and they are in their native range!  The shear numbers alone would make this video worth watching, but the movement of each individual within each group, and the coordination of the different groups on top of that, makes this simply breathtaking.

P.S. A group of Starlings is called a murmuration.

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At the field house where my lab and office is, we have a number of Barn Swallow pairs that build nests and raise young each year.  This spring has been no exception with about half-a-dozen pairs building their mud cup nests under the eves around the edges of the buildings.  One of these nests is right above the front door of the office building.  A pair (I don’t know if they are the same individuals) uses that nest every year, and again, this year is no exception.  It is pretty dramatic to have these incredible flyers zooming in and out right over my head every time I go in or out of the building.  I would think that the regular flow of traffic would disturb the birds enough that they would not use this particular section of eves to nest under, but they do not seem to mind much.  They do fly off the nest each time someone passes by, but then they fly right back without delay.  Yesterday, I was coming out the front door, I found the two halves of a Barn Swallow egg laying on the ground directly beneath the nest .  It was split neatly in half, which is a sure sign that it broke when the chick hatched out.

Baby birds use their egg tooth to slowly chip away and weaken the shell from the inside.  They do this by shifting around inside the egg such that their head moves along the equator of the egg.  As they go around and around on the inside their egg tooth moves around and around along the same line eventually causing the egg to crack around the middle leaving the shell in two tidy halves.

I did not see these shell fragments when I first got the field house about three hours before, and so am pretty sure that one of the Barn Swallow eggs hatched between 11am and 1pm yesterday.  It is kind of cool to have such exact information on hatching times.  The adults will soon be even more fun to watch as they whip back and forth to feed their newly hatched babies!

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Two friends, my wife, and I escaped the burgeoning heat of the central valley for the cool of the mountains to spend a beautiful weekend camping in the Sierra.  We drove up CA-4 Friday evening to the Pine Marten Campground on the east side of Lake Alpine which is at just over 7300 ft.  It was late by the time we arrived, and so we set up our camp in the dark and fell asleep listening to the hooting of a Great Horned Owl.  Set in Pines and Firs, this lake was a lovely spot to spend some time.  The first morning, I was walking at the edge of the lake and listening to the dawn chorus.  The American Robins started first.  There must have been several hundred of them in the area because the cacophony of their singing was amazing!  The next to join in was the trilling of the Dark-eyed Juncos.  Then came Mountain Chickadee, Pine Siskin, Brown Creeper, Western Tanager, and Mountain White-crowned Sparrow.  A few minutes later these were joined by Red-breasted Nuthatch, Yellow-rumped Warbler, and Stellar’s Jay.  The last to make themselves known were Mourning Dove and Douglas’s Tree Squirrel!  On the lake were several pairs of Canada Goose with young goslings in tow and a flock of maybe 30 Common Merganser, and over the lake I saw an Osprey searching for its breakfast.  I also saw a Bald Eagle who was sitting about 20 feet up in a tree when I came around the side of a large boulder, and was just as surprised to see it as it was to see me!  I also saw a Stellar’s Jay, across a narrow arm of the lake, that was carrying a stick in its beak.  As I watched, it flew to a cluster of small Lodgepole Pines right at the lakes’ edge.  It then dropped deep into the middle of the stand of trees to a mass of stickes that was its nest.  The nest was only about 15 ft off the ground.  Somehow, I expected it to be much higher.

We took a drive up to Highland Lakes which are just below tree line at about 8600 ft.  The road up to these spectacular lakes and the lovely campground between them is very rough, certainly needing a 4WD vehicle.  It passes the Bloomfield Campground, which is another lovely looking spot, and also passes a cluster of cabins high beside a wet mountain meadow.  On the way up, we saw a pair of Pine Grosbeaks, a Willow Flycatcher, a Yellow Warbler, and a flock of Cassin’s Finches.  The female finches were furiously gathering nesting material, and in the short time we stopped along the road, I found two of their nests!  Up at the lake I also found a Mountain Bluebird nest.  We also saw a number of butterflies: Mourning Cloak, Western Tiger Swallowtail, a Question Mark, and some species of Sulfur that was bright yellow with a very distinct, dark trailing edge to it’s hindwings.

Back at Lake Alpine, we settled in for a relaxing evening in camp.  As we made a fire and cooked dinner a pair of Western Tanagers came working their way through the campground.  First the female appeared, foraging for insects in the lower branches of the trees an on the ground.  The male followed close behind her spending most of his time watching her, and only occasionally grabbing an insect for himself.  They both came quite close to us and our camp which allowed us to get a wonderful look at them.

The next morning was largely devoted to packing up camp and heading back down out of the mountains.  A great trip and certainly an area that I will revisit soon.

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