|
August 12, 2004  An Hour In The Mudburbs Imagine you are only three weeks old. You hang head down in a mud igloo 20 feet above the ground, which in this case is a rosy crushed gravel surface with a concrete apron for a pillow. Everything you’ve seen of life so far has been a topsy-turvy version of a hard-to-grasp world. Your attendant parent birds swoop in from an unseen dimension outside your scope of view bringing you sustenance in the form of mouthfuls of squashed flying insects from a source you have yet to experience. You gorge and gorge on the food items, crowding toward the light, the food, which comes to you and your siblings through a narrowed neck in the mud structure, the entrance to your dwelling. This is the early life of a Cliff Swallow nestling. And I, having time yesterday evening, a full glass of wine, and rock and roll music on the shop radio, spent an hour spying on the inhabitants of these mud pots while trying to get a sense of the rhythm of the feeding that was taking place. First of all, I didn’t plan this. I just happened to be standing in the doorway of the workshop aimlessly looking about me, the radio turned on, when, up in the peak of the roof, I noticed the activities of the Cliff Swallows as they steadily came and went, attending to the feeding of their nestlings. It was 5 PM, August 9th. An hour of classic rock music was about to begin on the local radio station. A note pad next to a rotary phone in the shop and a sharpened pencil seemed to say, "We’ll help you document," and so began my hour of Cliff Swallow score keeping. What helped focus my attention was there were only four active nests in the surrounding outbuildings that, earlier in the year, swarmed with nesting Cliff Swallows. Now the only active nests were clustered in the peak of the roof, in an area no bigger than nine square feet. The rest of the Cliff Swallow colony, over 100 birds, fledged their young and left to fly towards California or further south. What I intended to do was assign a number to each of the four nests above me and keep track of the frequency with which the parent birds brought food to each. As I jotted down numbers I knew it was possible that this information might be fodder for a bird column. I was also aware that a list of numbers, regardless how meticulously recorded, might seem like a rather uninteresting way to describe an hour in the life of the Cliff Swallows. What the heck, I thought, it’s summer and everyone else is off holidaying. Who’s reading my column at this time of year anyway? So I began my list. What follows is the sequence with which parent birds of four active Cliff Swallow adults brought food to their young. The four nests are virtually joined. I numbered them 1, 2, 3, and 4 (this weeks illustration shows the nest layouts.) Here is the first sequence of visits by a parent bird with food for the young: #2, #2, #3, # 2, #4, #1, #2, #3, #3, #4, #2, #1, #3. This activity took place within 20 minutes. It doesn’t take a brain surgeon to realize the nestlings in #4 are getting less food than the other nests. Number 1 also isn’t doing very well. Two and three obviously have very attentive parents. So far, as the radio goes, I’ve heard CCR’s "Bad Moon Rising" and ZZ Top’s "Gimme All Your Loving." I’ve also watched two immature bald Eagles rising on a thermal to the North. I noted a fecal drop from nest #4 at 5:25. So far the first 25 minutes had flown by. I guess time flies when you’re watching fecal drops! With the time noted every minute or so I pressed on. Here is the next sequence of visits by adult birds: #2, #3, #2, #1, #2, #1, #2, #2, #1, #4, #3, #2, #1, #2. The time was now 5:31. The Who have been playing for several minutes on the radio and are still asking ‘Who needs you?’ During the last sequence of feedings there was a fly in by a number of adult birds, some of which never fed nestlings just fluttered about, making it very confusing in documenting which went to which nest. I was only trying to record actual visits with food. For the first time I notice the Who song contains some interesting lyrics. A clicking grasshopper sputtered past the shop door, a shadow of its former July self, now barely able to maintain the occasional click. I notice my neck was getting quite stiff from peering upward. I decided to let the nestlings increased chatter cue me to the return of an adult bird to rest the afflicted area. A song with the line ‘.....clowns to the left of me, jokers to the right’ begins as I note the time. It’s 5:31:30 and I write the next sequence: #3, #1, #2, #1 and #4 at the same time, now another #4. The sun was slowly moving around the shop as I made my notes and now my white t-shirt, once in the shade of the door opening was shining like a beacon. Some of the incoming adult Cliff Swallows give an alarm call, one that I know well from childhood. Whenever we stood under Cliff Swallow nests, most often on the bunkhouses in the company town where we lived, the Cliff Swallows would begin an alarm call that sounded to us like 'kids!... kids!' , which made sense since we were in fact kids and the Swallows didn’t trust us. Seeing my T-shirt the Swallows were now calling ‘kids!’ just as they did then. I pulled back inside the door. Unhindered feeding resumed. It was now 5:45. I know I’ve forgotten to note the songs that have played but I reminded myself that I was here for science, not for partying. I carried on with my list: #3, #4, #1, #1, #3. During this sequence I noted a very interesting nestling behaviour. Imagine if you will, the predicament of the nestlings in their cramped living quarters. Four young birds, confined to a mud nest about the size of a litre wine bottle, are fed constantly for three weeks, and, as a result of all that feeding find it necessary to void their innards frequently. The obvious question is where is all that fecal matter going to go? The nest would be full in days. For the first few weeks the attentive parents carried the droppings away each time they brought food, but now that the nestlings are larger they had a new tactic that I had not seen demonstrated until now. After a parent bird left I noticed some jiggling around in the nest. Suddenly I could see the tail end of one of the nestling. It positioned its rear end so that when it expelled the dropping, it fell through the narrow opening and out onto the ground. This action totally surprised me and being an instinctive act, gave me a totally new description of a Cliff Swallow nest. A Cliff Swallow nest is in form a mud flush toilet bowl stuck firmly to a flat surface by the area that would normally be the seat portion. The exit hole of the nest was the drain of the bowl and all that was missing from the toilet bowl structure was the pedestal on which a flush toilet stood. The young Swallows were essentially nestled down in a toilet bowl peering out through the drain. I found that observation was quite refreshing. About six o’clock, the end of my note taking, virtually every parent bird came flying in, fluttering and calling. It was visual pandemonium and luckily I was off the hook to record it. But now to my findings, because I know that’s what you’ve all been waiting for. The total number of visits by about 8 adult birds, delivering food to four nests in 60 minutes was 44. Nest #1 received 10 visits, nest #2 got 13 visits, nest #3 got 11 visits and nest #4 got 10. Obviously nest # 2 got more attention. This particular nest contained nestlings that I surmised were ready to fly. The entrances to #1 and #3 were too obscured to view but judging by the sounds coming from them I’d say they contained very young birds. Nest # 4 had young peaking out at about the same stage of development as #2. After I’d finished my impromptu survey I stood on the deck about a half hour later and was lucky enough to see one of the juvenile Cliff Swallows take its maiden flight from one of the nests I watched. It wasn’t a long trip, about 8 feet over to a slot in the eaves. From that vantage the young bird called and called to be fed but no parent bird would heed its cries. Growing impatient it launched itself in what I though might be a plummet to earth and though it did fly straight toward the ground at first, it turned the suicidal drop into a graceful curve from which it bore straight upward strongly and darted out over the driveway flying acrobatically through the evening air. It flew so well that I lost it among the adult birds that were still plying the air for insects. So long little mud toilet, I imagined it saying. From now on it would have the blue skies from which to drop its recycled bugs. To e-mail Tom CLICK HERE To look at previous column CLICK HERE |
