Why Environmental Policy Nightmares Recur

Many natural resource and environmental policy issues evidence recurring choices, made with considerable effort, whose temporary solutions never seem to deal with the underlying problems. Drawing on examples from endangered species policy, I describe five behavioral tendencies of humans and human institutions that result in recurrent environmental policy problems, including poor long-term direction, delays, impasses, and piecemeal solutions to crosscutting problems. These tendencies are short-term rationality outcompeting long-term rationality, competitive behavior driving out cooperative behavior, fragmentation of interests and values, fragmentation of responsibilities and authorities, and fragmentation of information and knowledge. By understanding these tendencies, it is possible to frame policy solutions to them. This paper identifies a set of necessary responses including finding ways to bind current decisionmakers to the future, promoting creativity and risk-taking on the part of public resource management organizations, utilizing alternative dispute resolution mechanisms that foster cooperation, building political concurrence, utilizing coordinating mechanisms, instituting clear performance measures, and implementing ways to promote information flows between organizations.     

Mating behaviour of the tiger blue butterfly (Tarucus theophrastus): competitive mate-searching when not all females are captured

Summary Females of the tiger blue butterfly (Tarucus theophrastus) fly upwind in search of the larval hostplant. Males perch or patrol the downwind edges, searching for incoming females or those already on the bush. A model of competitive mate-searching is developed for the case where not all receptive females are contacted by searching males: the model differs from the earlier ones of Parker (1970, 1974), particularly when few males are involved. Observed distributions of males upon bushes of different sizes agree better with the predictions of the game theory model than with a random distribution of males. The described model may be widely applicable to populations where females remate, but frequently evade detection by searching males.     

Vigilance and foraging substrate: anti-predatory considerations in a non-standard environment

Summary The commonly studied standard anti-predatory environment presents animals with spatially-distinct feeding sites and refuges from attack, neither of which necessarily obstructs predator detection. In contrast, tree-trunks provide animals with a markedly non-standard environment in which the foraging substrate itself may be a refuge from attack that unavoidably obstructs predator detection. Thus anti-predatory behavior in this environment should be influenced not only by a perceived risk of attack, but also by the nature of the refuge/foraging substrate itself. Downy woodpeckers (Picoides pubescens) are a common tree-trunk foraging animal, and an experimental analysis of their behavior suggests that they respond appropriately to their non-standard anti-predatory environment. In particular, anti-predatory vigilance varies strongly with changes in tree trunk diameter. Two modes of vigilance were apparent. In stationary vigilance, woodpeckers maintained the position of their feet while rotating their bodies side-to-side to peer around the trunk; mobile vigilance involved movement around the trunk itself. Both the frequency and angle of rotation of stationary vigilance increased with trunk diameter, as did the frequency of mobile vigilance. The woodpeckers also held their heads farther away from the trunk surface as diameter increased. All of these measures of vigilance increased under a greater perceived risk of predation. As might be expected given these results, downy woodpeckers avoided thick trunks; they did not, however, prefer the thinnest (least obstructive) available trunks. These preferences may reflect the influence of trunk diameter on thermo-ecological and/or anti-predator considerations not related to vigilance. Overall, this arboreal environment provides an unusual perspective on anti-predator decision-making with several implications for tree-trunk foraging animals in general.     

ESTIMATING CENTRAL TENDENCY FROM UNCENSORED TRACE LEVEL MEASUREMENTS1

ABSTRACT: The statistical analysis of data which have trace level measurements has traditionally been a two-step process in which data are first censored using criteria based on measurement precision, and then analyzed with statistical methods for censored data. The process might be more informative if data were left uncensored. In this paper, information loss attributable to censoring and measurement noise are assessed by comparing the sample mean and median of uncensored measurements with a log regression mean and median based on censored data. Measurements are derived from lognormal parent distributions which have random variability characteristic of trace level measurement. The relative performance of estimators used with error-free samples and with samples having measurement noise can be explained by differences between the probability distributions of parents and measurements. Measurement introduces bias and dispersion and transforms lognormal parent distributions toward greater symmetry. Estimates using uncensored data are less biased and more accurate than the log regression mean and median when censoring exceeds about 50 percent, and are not much worse at any fraction censored. For data with many (80 percent) results below the limit of detection, bias may be quite severe.     

Prenatal diagnosis of trisomy for the distal two-thirds of the long arm of chromosome 14 (q21→qter)

A de novo case of ‘pure’ trisomy 14q21 → qter is described which was detected at amniocentesis following an abnormal ultrasound scan of a 25–year-old woman. This is apparently the largest distal 14q duplication reported in a case surviving beyond the first trimester. The infant apipeared to have an association of clinical abnormalities previously observed in distal 14q trisomy and proximal 14q trisomy/mosaic trisomy 14.     

Low Genetic Variability in the Hawaiian Monk Seal

The Hawaiian monk seal (   Monachus schauinslandi) is a critically endangered species that has failed to recover from human exploitation despite decades of protection and ongoing management efforts designed to increase population growth. The seals breed at five principal locations in the northwestern Hawaiian islands, and inter-island migration is limited. Genetic variation in this species is expected to be low due to a recent population bottleneck and probable inbreeding within small subpopulations. To test the hypothesis that small population size and strong site fidelity has led to low within-island genetic variability and significant between-island differentiation, we used two independent approaches to quantify genetic variation both within and among the principal subpopulations. Mitochondrial control region and tRNA gene sequences (359 base pairs) were obtained from 50 seals and revealed very low genetic diversity (0.6% variable sites), with no evidence of subpopulation differentiation. Multilocus DNA fingerprints from 22 individuals also indicated low genetic variation in at least some subpopulations (band-sharing values for "unrelated" seals from the same island ranged from 49 to 73%). This method also provided preliminary evidence of population subdivision (  F'_st estimates of 0.20 and 0.13 for two adjacent island pairs). Translocations of seals among islands may therefore have the potential to relieve local inbreeding and possibly to reduce the total amount of variation preserved in the population. Genetic variation is only one of many factors that determine the ability of an endangered species to recover. Maintenance of existing genetic diversity, however, remains an important priority for conservation programs because of the possibility of increased disease resistance in more variable populations and the chance that inbreeding depression may only be manifest under adverse environmental conditions.     

Relationship of Effective to Census Size in Fluctuating Populations

Abstract: The effective size of a population (    N _e   ) rather than the census size (    N ) determines its rate of genetic drift. Knowing the ratio of effective to census size, N _e  /   N , is useful for estimating the effective size of a population from census data and for examining how different ecological factors influence effective size. Two different multigenerational ratios have been used in the literature based on either the arithmetic mean or the harmonic mean in the denominator. We clarify the interpretation and meaning of these ratios. The arithmetic mean N _e  /   N ratio compares the total number of real individuals to the long-term effective size of the population. The harmonic mean N _e  /   N ratio summarizes variation in the N _e  /   N ratio for each generation. In addition, we show that the ratio of the harmonic mean population size to the arithmetic mean population size provides a useful measure of how much fluctuation in size reduced the effective size of a population. We discuss applications of these ratios and emphasize how to use the harmonic mean N _e  /   N ratio to estimate the effective size of a population over a period of time for which census counts have been collected.     

A survey of drinking water supplies in the Province of Ontario for dioxins and furans

A survey of drinking water supplies in the Province of Ontario was initiated in 1983 to determine the extent of their contamination by polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). This drinking water survey arose from concerns regarding the discovery of PCDDs and PCDFs in sport fish from western Lake Ontario in the early 1980's.A total of 49 water supplies throughout all Regions of Ontario have been examined to date. Water supplies in the vicinity of chemical industries and pulp and paper mills were sampled more frequently; as many as 20 times. Detection limits were in the low parts per quadrillion (ppq) range for all tetra- to octachlorinated PCDDs and PCDFs.As of February 1989, 4, 347 results were received for 399 raw and treated water samples. Only 37 positive results were reported, constituting less than 1 percent of the total number of results. The O₈CDD congener accounted for 36 of the 37 positive results. The 2,3,7,8- TCDD isomer was not detected in any sample.