Around the cabin walls are mementoes of two trips to India. At one of the meetings there reviewing wildlife research, I heard a person in the audience ask, "Why ring birds?" (Ringing means putting a light-weight metal bracelet, a ring, or band on the leg of a bird.) There was silence, then nervous laughter, then silence. The question was greeted like that of a child: "Why is auntie's nose so big?" It is the kind of question that is just not asked! Of course, it is the kind of question that needs to be asked, but it was rare. It is the kind asked by skeptical scientists, by journalists, and by good politicians trying to get to the root of social issues. It is the major type of question needed for the very difficult problem of spending paltry amounts of money on ponderous wildlife issues. In the answer is recognizing some of the differences between wildlife research and wildlife management. In one there is an emphasis on analysis, on system outputs, and description of things as they are. In the other, the emphasis is on design, on system objectives, and on things as they might become.

I was surprised that more answers were not readily given to "Why ring birds?" in the meeting. In retrospect, given the country, conditions, and training of the people assembled, I should not have been surprised. The reason then given was identical to my first reason.

Reason #1

Just because! These two words are the answer to all questions of "why?" by people engaged in basic research. Because I am curious; because I can do it; because something new may be learned; just because! The answer is similar to that for the question put to mountain climbers. Why climb the mountains? The answer: Because it is there!

Reason #2

Figure 8.1. By progressively plotting over the year the maximum distance that a species of bird has flown, a projection can be cast to a maximum likely value.

We ring because we want to know how far birds fly. Curiosity raises its head again. What will you do with the answer if you had it? You ring a bird; it is captured. You measure the distance on a map. It is a straight line - a minimum estimate at best. You measure all distances from ringing point to capture or rediscovery of the ring. Now you compute the average, median, and maximum distance. (The minimum has no meaning.) You sort them high to low, then use mathematics and a small computer to cast the line to the next "theoretical bird distance." This suggests the maximum ever likely to be seen. Another researcher watches the distances as they come in lab reports each year and, like a person watching the flood stage on a mighty river, plots the time at which the next greater distance is reported. Eventually the curve levels off (Fig 8.1) and it is possible to cast a line to the maximum distance. Now we have actual records and two theoretical grounds for knowing the straight-line distances (all minimum, but at least an index and probably comparable), but the long-range flyers probably have more deviation in their numbers than the short-distance flyers.

Interesting! So what?! Poor and hungry people cannot afford to feed your curiosity, scientist. Distance estimates allow scientists to understand the food use efficiency of birds, to compare aircraft efficiencies for improved design, to draw zones from which India (or any other region of the world) may receive inputs by bird flight of disease organisms, parasites, and transfer of other animal (e.g., snails and plant seeds {e.g., weeds}). Distance measures help us understand our relations with other countries, annually "stitched together" by short and long flights of birds from all communities exchanging the energy from insects eaten south with the proteins gathered in the north. Sadly, it tells of how toxicants are traded and mixed after they are consumed east and west.

Reason #3 Ringing tells us about an area's bird resource. What birds are truly those of the region? How many spend how many months each. Is the region the bedroom community for birds, a temporary place? Maybe the area is the central place and other places in other countries meet short-term needs.

Understanding short-term needs for animals is akin to understanding the importance of a small gland in the body. Size or duration is irrelevant; only presence is important, for with presence comes some essential function. A small marsh for resting may be essential to birds making a long flight. There may be other marshes; there may have been many wet areas a month ago, but not during the height of migration, a small wet place properly placed for its historical role is essential for a large population to return in health to its wintering or nesting grounds.

Ringing tells source and destination, and pathway and highlights critical areas. If any country wants birds, it must manage them throughout their entire life areas. Managers cannot do select work in a region and assume that all solutions will fall into place elsewhere any more than a skin doctor can assume nutrition will be taken care of by the patient or another doctor. Ringing tells the extent of the management responsibility. It allow mapping, on a species-specific basis, of the life area for sophisticated management of habitats, the populations itself, and people who may benefit from the resource.

Reason #4

Ringing is done to find out what conditions or habitats are needed or used by each species. Rings consistently found and only reported in one type of forest suggest a habitat-dependent species. An observer may only study birds in a forest, suspect it lives elsewhere and in other habitats, but only by long-term, consistent ringing does the truth of the habitat requirements become known.

Reason #5

We ring birds for courtroom protection. More people spend time in courts than in the fields and forests enjoying wildlife. There is a real danger that a country or region will be sued, will have some kind of legal action taken against them, if the migrating birds are killed or endangered by some military, industrial, or other action. The rings will prove "these are not our birds!" or, to the contrary, "you have killed our birds." We live in a world full of lawyers, more full of potential clients, ready to go to court - sometimes for very good reasons. The abnormal loss of wildlife due to human carelessness or ignorance can be brought to courts. Rings can be a part of the court proceedings - either for the defense or prosecution.

Reason #6

A trick of mathematics, a ratio procedure, allows rings to be used in estimating population size. There are many large books on estimating wildlife populations, but the theory is found in the following ratio, where M is all the ringed or marked animals in the wild, N is the unknown number in the population, n is the number of birds in a sample (in a net or seen with binoculars), and m the ringed birds in the sample. With a little algebra:

M / N = m / n

and thus

N = Mn/m

and an estimate of N is made when values of M, m, and n are inserted.

Reason #7

Rings recovered and reported can give some insight into changes in population size (as estimated above) over time. After adjusting for new numbers of birds ringed and probable deaths or losses based on life expectancy, then reports over many years can suggest trends. Caution is needed. Where intensive sampling is done in a standard fashion, the proportion of ringed birds in the annual catch can be very useful. The question remains: Is the high cost of a very gross estimate for one or two species worth it when there are over 1,000 species? Can the results from a few species be generalized to most of them? Other types of studies of trends are probably needed.

To conserve or manage any bird species, you must know almost everything about its natural history and life. Ringing identifies birds, allows energy spent and habitats used to be determined; accidents or mortality appraised; and dependencies to be established. Rings show up in predator feces and stomachs showing us what birds are eaten, by which animals, and where, after how long a life.

Hunting of birds, particularly waterfowl, when carefully regulated, can allow sustained populations of such birds to exist. The condition of "careful regulation" is based, in part, on information supplied by hunters and hunting area managers who report time and areas within which birds are taken. Knowledge of numbers of birds that are ringed, locations, flight patterns, hunting pressure, as well as sex and age of birds give a good picture of the dynamics of the resource.

Ringing is done to find out the areas where bird management can be most effective. If more than species X is desired, then wildlife managers must learn where to stop losses, improve or stop loss of nesting habitat, improve pre-migration energy supplies, or manage for the lowest costs.

Many people only want a single "bottom line" or the answer, so many reasons why ringing is done may not please them. I am prone to argue that one reason is rarely enough for the skeptic or critic. Many seems convincing, even though I expect several to be discounted in making any argument for a practice.