Male's return rate, rather than territory fidelity and breeding dispersal, explains geographic variation in song sharing in two populations of an oscine passerine (Oreothlypis celata)

Males of some oscine passerines learn and share songs of neighboring males. This process can lead to the formation of song pattern neighborhoods or microhabitat song dialects. The degree to which song sharing occurs between populations and the spatial scale over which neighboring males share songs, however, can vary widely, and interpopulation comparisons have suggested that song sharing is more common in residents than in migrants. Here, we examine two populations of the orange-crowned warbler (Oreothlypis celata) to quantify patterns of song sharing at the northern (long-distance migrant) and southern (short-distance migrant) edges of the breeding distribution and to test if return rate, territory fidelity, and breeding dispersal explain the patterns found in the two populations. The southern population (O. celata sordida breeding on Santa Catalina Island, California; 33°N) had a higher annual return rate to their territories and exhibited higher song sharing in neighborhoods than their counterparts (O. celata celata breeding in Fairbanks, Alaska; 64°N). Year-to-year patterns of territory fidelity and breeding dispersal distances were similar between populations. Our results suggest that if migratory distance generally covaries with the proportion of returning males, this could explain different levels of song sharing between the short- and long-distance migrants.     

The use of digital photos to assess visual cover for wildlife in rangelands

Grassland vegetation can provide visual cover for terrestrial vertebrates. The most commonly used method to assess visual cover is the Robel pole. We test the use of digital photography as a more accurate and repeatable method. We assessed the digital photography method on four forage grassland species (Pseudoroegneria spicata, Festuca campestris, Poa pratensis, Achnatherum richardsonii). Digital photos of 2-dimensional cutout silhouettes of three bird species sharp-tailed grouse, western meadowlark and savannah sparrow were used to model the impact of clipping (i.e., grazing) on visual cover. In addition, photos of artificial voles were used to model litter on cover available to small mammals. Nine sites were sampled and data were analyzed by the dominant grass species in each study plot. Regression analysis showed that digital photos (r² = 0.62) were a better predictor than the Robel pole (r² = 0.26) for assessment of cover. Clipping heights showed that clipping at less than 15 cm left the silhouettes 50% exposed. Digital photo analysis revealed that visual cover was affected by the type of grass species, with F. campestris > P. pratensis > A. richardsonii > P. spicata. Biomass and litter were both positively related to cover for small mammals.     

Experience affects mating behavior, but does not impact parental reproductive allocation in a lizard

Investment into reproduction is influenced by multiple factors and varies substantially between males and females. Theory predicts that males should adjust their ejaculate size or quality in response to variation in female experience or phenotypic quality. In addition, sperm investment by males may also be influenced by their own status and experience. Although such adjustments of male ejaculate size can impact reproductive success (via fertilization success), fitness returns from male sperm investment may be influenced (either limited or facilitated) by the level of maternal investment. To test this hypothesis, we conducted an experiment that simultaneously evaluated the effect of paternal and maternal experience (which incorporates mating status, age, body size, and other related variables) on paternal sperm investment and maternal reproductive allocation in the lizard Anolis sagrei. During staged mating trials, experienced males were more likely to copulate with females, but these individuals were less likely to transfer sperm during mating than were naïve individuals. Maternal experience had no impact on these mating behaviors. In contrast to expectations, experience and phenotypic quality (of both sexes) had no impact on male ejaculate size or quality (proportion of live sperm) or on maternal reproductive investment (in terms of egg size and yolk steroids). These findings were intriguing given the mating system and past evidence for differential maternal investment in relation to sire quality in A. sagrei. The results found in this study highlight the complexity of reproductive investment patterns, and we urge caution when applying general conclusions across populations or taxa.     

Fungal inoculum properties: extracellular enzyme expression and pentachlorophenol removal by New Zealand trametes species in contaminated field soils

This study was conducted to improve the ability of indigenous New Zealand white-rot fungi to remove pentachlorophenol (PCP) from contaminated field soil. The effects of different bioaugmentation conditions on PCP removal and extracellular enzyme expression were measured in the laboratory. The conditions were fungal growth substrate and co-substrate composition, culture age, and Tween 80 addition to the contaminated soil. The fungi used were Trametes versicolor isolate HR131 and Trametes sp. isolate HR577. Maximum PCP removal was 70% after 7 wk from a 1043 mg kg(-1) PCP-contaminated soil inoculated with an 11-d-old fungal culture of T. versicolor isolate HR131. There was minimal production of undesirable pentachloroanisole by the fungi. Tween 80 addition had no affect on PCP removal. Poplar sawdust was more suitable as a fungal growth substrate and a co-substrate amendment for PCP removal and extracellular enzyme expression than the locally available pine and fir sawdust. Pentachlorophenol removal was not necessarily correlated with extracellular enzyme expression. The research results demonstrate that PCP biodegradation was affected by inoculum culture age, by the presence of a co-substrate amendment, and by growth substrate composition after white-rot fungal bioaugmentation into PCP-contaminated field soils.     

RCRA leapfrog: How statistics shape and in turn are shaped by regulatory mandates

During the past ten years, a statistical program applicable to RCRA groundwater monitoring data has been developed with input from regulators, geologists, regulated individuals, and a small group of professional statisticians. At first driven by the RCRA regulations, the evolution of the statistical program now often influences changes in regulatory requirements, which in turn affect opinions on the best statistical approach for addressing the requirements. This article describes that evolution and the issues that have emerged over the years. In the following article, Dr. Robert Gibbons, another of the professional statisticians involved in the debate, responds to comments made in this article.     

Risk analysis of the 1970 san antonio diphtheria epidemic*

Prediction of disease patterns for communicable diseases with low prevalence rates is difficult because of the random variations inherent in the data Smoothing of prevalence or incidence data prior to the analysis may facilitate these predictions. All of the analyses are based on census tract characterisiics. The disadvantages of this type of data are that the boundaries are arbitraty and lead to some heterogenous tracts. Also, the analyses depend totally on aggregate rather than individual data. The advantage of working with this type of data is its availability for all metropolitan areas. The San Antonio diphtheria epidemic has been previously referred to as an ethnic epidemic. This paper shows that it is even more an epidemic of lower socioeconomic groups. In this region of the country, socioeconomic characteristics are almost indistinguishable.     

Book reviews

“Water Planning and the Regions”

Edited by P. J. Purdy, R. S. A.

Discussion Paper No. 9, 1977, £1.50.

Tenant participation in council housing management; Housing Development.

Directorate Occasional Paper 2/77, DoE London, 1977.

Getting tenants involved: a handbook on systems of tenant participation in housing management; DoE London, 1977.

La politica dei servizi tra razionalizzazione e rinnovamento

Alberto L'Abate (1978)

Marsilio Editori, Padova, pp. 316

Handbook for Environmental Planning: the social consequences of environmental change.

J. McEnvoy & T. Dietz (1977)

New York, J. Wiley, pp. 323. Price £15.50

Planning and Urbanism in China

Progress in Planning Vol. 8, Part 2, Fo. 1 N. Jeffrey and M. Caldwell, pp. 97–182, 1977

Pergamen, £4.00

The European Community's Regional Fund

Ross B. Talbot

Progress in Planning, Vol. 8, Part 3, pp. 183–281

Pergamon Press, 1977

Providing the Posh Words

W. Hampton, DoE

1978. £1.50. 60pp.

Four Titles on Conservation

A Critical Bibliography of Building Conservation. John F. Smith. Mansell, London 1978. 207 pages including index. Hard back, £12.90.

Conservation and Planning. Alan Doby. Hutchinson — The Built Environment. 1978. 173 pages. Some illustrations. Paper back, £3.25.

A Study in Conservation. Winston Barnett and Cyril Winskell. Oriel Press, 1977. 45 pages, in English, French and German. Illustrated. Paper back, £3.75.

Interpreting the Conserved Environment. Working Paper No. 29. Brian Goodey. Oxford Polytechnic Department of Town and Country Planning, 1977. 65 pages. Paper back, not priced.

“Belgium”, R. Riley, £3.25, 205 pp.

“The Netherlands”, D. Pinder, £3.25, 194 pp.

“The USSR”, J. C. Dewdney, £3.25, 262 pp.

Development Strategy of Bangladesh

Nurul Islam

Oxford, Pergamon Press, 1978, 109 pp.     

Biochemical and energetic composition of bathyal echinoids and an asteroid,holothuroid and crinoid from the Bahamas

The biochemical and energetic composition of body components of ten species of bathyal echinoids, and an asteroid, a holothuroid and a stalked crinoid were determined from individuals sampled from a variety of deep-water sites near the Bahamas (north Caribbean Sea) in October 1988. When compared with other studies of echinoderms, no geographic- or depth-related differences in biochemical or energetic composition were found. Body-wall tissues were composed primarily of skeletal material (mineral ash), but were comparatively high in organic material in the echinothuriid echinoids, and the asteroid and holothuroid. Gut tissues and pyloric cecae had high levels of lipid and protein, indicating their potential role in nutrient storage. Body-wall tissues were generally low in energy, but were highest in the echinoidsAraeosoma belli (7.7 kJ g^–1 dry wt) andSperosoma antillense (8.0 kJ g^–1 dry wt), the asteroidOphidiaster alexandri (8.9 kJ g^–1 dry wt), and the holothuroidEostichopus regalis (13.1 kJ g^–1 dry wt). Energy levels of gut and pyloric cecal tissues were two to three times higher than those of body-wall tissues. Total somatic tissue energy values varied greatly among species, ranging from 1.5 kJ in the echinoidAspidodiadema jacobyi to 142.1 kJ inE. regalis. As the bathyal echinoderms examined in this study occur in great abundance, they represent a significant reservoir of organic and inorganic materials and energy in deep-water benthic systems.     

Some experiences in hazard identification and risk shortlisting

‘Rapid ranking’ has been used for many years as a method of determining the priority which should be given to formal investigation of the wide range of hazards and risks present on major process industry sites. Such methods tend to evolve to meet the needs of specific applications. Some historical and recent applications are outlined, and the nature of the developments which they led to are discussed. Particular topics discussed include: development of the method such that it is usable by operating managers rather than specialists; use to raise risk consciousness; adaptation for use as an aid to hazard identification; use to define both which risks should be studied and which risks, even if low, should be incorporated in routine monitoring and periodic auditing programmes; use as a basis for comparison of the relative risks presented by a variety of different industrial installations; use for a range of different types of risk; and extension beyond ranking to include ‘shortlisting’ i.e. deciding which risks to include in a study programme and which to leave out. Philosophical difficulties with the approach are discussed, including the danger of omitting from detailed study a risk which is erroneously shown as low, and the uncertainty of the absolute level of the ranked risks. Approaches to minimizing these problems are discussed.