North Temperate Regions Research Articles

Characterization of the Rampur Bushair sheep in the north temperate region of India

SummaryRampur Bushair is an important dual-purpose (meat and wool) sheep in the north temperate Himalayan region of Himachal Pradesh state (India). The breeding tract of the breed runs across three districts namely Lahaul Spiti, Kinnaur and Shimla in Himachal Pradesh. Information on three body biometric characteristics, viz. body length from shoulder to pin bone, chest girth and height at wither, qualitative confirmation attributes and body weights of 335 animals were recorded. Animals were strong, well-built and of medium size with a square brow. The animals were mostly white, but black, brown and mottled were also found in good numbers. Typically a prominent Roman nose, convex head, large eyes and pendulous ears (10 cm to 15 cm long) with a prominent mid-ridge were peculiar characteristics of this breed. The males had medium to long (19 cm to 29 cm) curling horns, running backwards and downwards. The ewes were polled. The average adult body weight of males was 34.7 kg and that of females was 26.0 kg. The body weight of adult male and female sheep varied from 24 kg to 47 kg and 18 kg to 40 kg, respectively. Wool yield varied from 200 g to 500 g per shearing. The animals were shorn twice a year (summer and winter). Sexual maturity in males and females is reached at one year of age.The information on feed, management and breeding practices, flock size and structure, reproductive performance and disease prevalence in the breeding tract was collected through formal interviews, using a structured questionnaire given to sheep owners, who were chosen at random within a structured, stratified framework. There were 98 574 animals of the Rampur Bushair sheep breed in its breeding tract based on the sample survey estimates. The results indicated good scope for improvement of its productivity under the field conditions based on selective breeding.

Selective sweeps and intercontinental migration in the cosmopolitan moss Ceratodon purpureus (Hedw.) Brid.

The moss Ceratodon purpureus has long been used as a model system in plant development and physiology. However, the molecular population genetics of the species remains virtually unexplored. In this study, we used population genetic analyses of DNA sequence data from three unlinked loci (atpB-rbcL spacer, adk, and phy2) to examine biogeographical patterns in a global sample of this species. The three loci differed significantly in mutation frequency spectra and implied population structure. Pairs of haplotypes from single populations were frequently more divergent than haplotypes sampled from widely disjunct populations. In the atpB-rbcL spacer and adk samples, Australasian haplotypes were more closely related to Northern Hemisphere haplotypes than to haplotypes found in the equatorial regions. In contrast, the phy2 sample showed that the north and south temperate regions were genetically divergent, with the equatorial regions intermediate. Maximum-likelihood estimates (MLE) of the rates of migration between the two hemispheres were significantly different for the two nuclear genes. The frequency spectra of mutations indicated that differences in implied population structure among the three loci resulted from directional selection on the chloroplast genome and on the chromosomal segment containing adk. Collectively, these data suggest that long-distance migration within the Northern Hemisphere and Australasian regions is common (relative to the mutation rate) and that migration between these two regions, potentially via equatorial populations, is more frequent than migration among equatorial populations.

New species and records of Laboulbeniales from the subantarctic islands of New Zealand

Until now Rhachomyces kenodactyli Balazuc & W. Rossi has been the only species of Laboulbeniales known to occur on Coleoptera in the Bounty, Antipodes, Auckland, Campbell and Snares Islands, which lie 48° to 35° S. Four new species (Diphymyces depressus, Diphymyces leschenii, Laboulbenia subantarctica and Laboulbenia loxomeri) and five new records for the subantarctic (Cucujomyces phycophilus, Diphymyces penicillifer, Laboulbenia sp. 1, Rhachomyces sp. 1 and Teratomyces sp. 1) are reported, increasing the known number of taxa tenfold. An expanded geographic range for Rhachomyces kenodactyli is reported. A relatively high percentage (12%) of known beetle species in the subantarctic serve as hosts for Laboulbeniales. This host utilization rate is higher than that in tropical and north temperate regions. The high proportion of intertidal coleopteran taxa in the subantarctic fauna probably accounts for the greater number of host species utilized. Fungi on intertidal beetles (Omaliinae [Staphylinidae], Oopterus [Carabidae] and Kenodactylus audouini [Carabidae]) are known from many host individuals and collections, while those on terrestrial species are known from few, and in some cases, a single collection or host. The sporadic occurrence of some species encountered increases the likelihood that a few species of Laboulbeniales on Coleoptera probably remain undiscovered in the region.

Surviving the ice: Northern refugia and postglacial colonization.

The contemporary distribution of biological diversity cannot be understood without knowledge of how organisms responded to the geological and climatic history of Earth. In particular, Quaternary expansions and contractions of glacial ice sheets are thought to have played an important role in shaping the distribution of biodiversity among current populations in the north-temperate region. In the central U.S., fossil and palynological data provide support for the maintenance of a large southeastern refuge during the last glacial maximum, and many temperate organisms are believed to have responded to glacial expansion by shifting their ranges to southern refugia and recolonizing northward to track the receding ice sheets. Thus, organisms are assumed to track favorable climates, and species ranges are expected to have shifted significantly. Here we present data from a deciduous forest vertebrate, the eastern chipmunk (Tamias striatus) in the central U.S., indicating the maintenance of multiple refugial sources as well as a southward expansion from a northern refugium. These results challenge the view that, during glacial maxima, organisms must have migrated south out of their ranges to track favorable climates.

Ecology of tree intercropping systems in the North temperate region: Experiences from southern Ontario, Canada

Agroforestry practices in northern latitudes, although less diverse than those in warmer regions, have unique advantages over conventional land-use systems in the region in terms of water-quality enhancement, carbon se-questration, and biodiversity conservation. Tree intercropping, especially, is a potentially promising agroforestry option in the region. Understanding the ecological interactions between trees and crops in such intercropped systems provides the basis for designing efficient systems with potential for wider applicability. With this objective, the experience from several years of research on this aspect at the University of Guelph, in southern Ontario, Canada are presented. Yields of C3 crops intercropped with trees, as well as growth of trees, did not differ from those in corresponding sole-stand (conventional) systems of crops and trees. But, soil organic carbon content and bird and insect diversity increased in the intercropped area. The abundance and distribution of earthworms were higher closer to the tree rows indicating improved soil health. The C sequestration potential in fast-growing tree (hybrid-poplar)-based intercropping systems was four times more than that reported for conventional agricultural fields in the region. Because of reduced fertilizer use and more efficient N-cycling, the tree-intercropping systems could also lead to the reduction of nitrous oxide emissions from agricultural fields by about 0.7 kg ha−1 yr−1. Marginal or degraded land that is suitable for agroforestry is estimated to be 57 million ha in Canada. Tree/crop intercropping is one agroforestry system that shows great potential for this region. We suggest that this land-management option can be placed above conventional agriculture in terms of long term-productivity and sustainability.

The dynamics of hunted Icelandic goose populations: a reassessment of the evidence

Summary Migratory geese are dominant terrestrial herbivores in Arctic and north temperate regions. They are important quarry species and also conflict with agricultural interests through winter foraging. We investigated the dynamics of the populations of greylag Anser anser and pink‐footed Anser brachyrhynchus geese that breed in Iceland and winter in Britain. We estimated seasonal and annual survival of both populations based on colour‐ringing programmes in Iceland 1996–2000 and in Britain since 1987. We used these results, along with hunting bag statistics from Iceland, in a set of models to assess the British autumn counts as well as the impact of hunting. After a rapid increase, the pink‐footed goose counts stabilized after 1992 at around 230 000. The greylag goose counts increased slowly to c. 100 000 around 1990 and then declined to around 80 000. Both populations showed stable counts from 1996 to 2000, when the proportion of young recorded in autumn was 17·5% for greylag geese and 18·2% for pink‐footed geese. Hunting bag statistics have been compiled since 1995 in Iceland; during 1996–2000, means of 36 608 greylag geese and 13 991 pink‐footed geese were reported shot annually. Mean annual adult and first‐year survival estimates were 0·727 and 0·472 for greylag geese, and 0·814 and 0·394 for pink‐footed geese. The lower survival of juvenile pink‐footed geese was probably due to higher natural mortality, whereas the generally lower survival of greylag geese could be explained by higher hunting pressure. Simple modelling showed that the results from autumn surveys and bag statistics were incompatible for greylag geese. For the population to remain stable with the estimated survival rate, the proportion of juveniles in autumn must be 30%. We suggest that problems in separating juveniles from adults in October–November caused the lower proportion of juveniles recorded. Also, the number of greylag geese counted in autumn and the number reported shot in Iceland cannot both be correct; the bag statistics imply a population twice as large as the number counted. Large numbers of greylag geese may winter in areas not covered by the autumn census, but overreporting of the hunting bag may also have occurred. No such discrepancies were found for pink‐footed geese. Synthesis and applications. We recommend that a stratified sampling programme be established for estimating the size and age composition of both goose species. The age composition of greylag geese can profitably be studied in Iceland in August, when juveniles are easily recognizable. Ringing should be continued as a tool for monitoring survival, and a hunting bag survey should be implemented in Britain. In general, the reliability of population surveys should always be tested with independent data.

African pollination studies: where are the gaps?

The literature on African pollination biology is reviewed. It is found that relatively little work has been done on pollination biology in Africa, and a very small proportion of pollination relationships has so far been studied. Much of the research which has been done is of an evolutionary nature. Very little work has been conducted at the community level and comparatively little applied work, either to agriculture or conservation, was encountered. Most research has been conducted in South Africa, in particular, from the Cape region, which is the only part of Africa for which a reasonably comprehensive body of work on pollination biology exists. In a number of instances results of African studies challenge conventional understanding of pollination biology. It is argued that as more work on pollination is done in Africa, more differences between African systems and the rest of the world, particularly the North temperate regions will be found and changes to the overall conceptualization of pollination systems in different ecosystems are likely to ensue. A more thorough understanding of pollination biology would also make an important contribution to food security and conservation of biodiversity on the continent. Scientists working in fields other than pollination biology, and amateurs, should be encouraged to contribute to the groundwork of African pollination biology by the documentation of pollination relationships.

Floristics and ecology of Myxomycetes in China 1. A tentative list of known species

Four hundred and twelve species of Myxomycetes were reported. The list basically reflects the present knowledge of the species diversity and geographical distribution of Myxomycetes in China. In China, the species diversity of Myxomycetes in the north temperate regions is well known, but that in the tropical and subtropical regions is still inadequately known and will become a key research point in the future.

The role of water-level fluctuations in shallow lake ecosystems – workshop conclusions

Discussion and conclusions are presented from a workshop held at Balatonfured, Hungary in May 2002 on the role of water-level fluctuations on the structure and function of shallow lakes. Water-level regime is regarded to be an important factor for lake ecosystem functioning and affects conservation values. Biota, in particular those living in vegetated areas, respond differentially to changes in hydroperiod dynamics. Extreme water levels may cause shifts between the turbid and the clear, macrophyte-dominated state. Strong effects of anthropogenic changes in the fluctuation of water levels are shown for Mediterranean (Greece, Turkey) and north temperate (The Netherlands) regions. Additionally, effects of climate change are anticipated that might alter the functioning of shallow lakes in these regions differentially. There is a need for data on the relationships between water-level changes and ecosystem responses. A plea is made for international cooperation and information exchange and an internet site for facilitating this has been developed.

The Evolution of Araliaceae: A Phylogenetic Analysis Based on ITS Sequences of Nuclear Ribosomal DNA

Phylogenetic analyses of ITS sequence data from 70 species and 40 genera of Araliaceae (representing all major lineages within the ''core group'' of the family) do not support the widely used traditional division of Araliaceae into three tribes. Tribe Aralieae (characterized by imbricate petals) is found nested within a paraphyletic Schefflerieae (whose taxa have valvate petals). There are, however, two large monophyletic groups comprising most araliad genera: the ''Aralia-Polyscias-Pseudopanax group'' (which in- cludes Aralia, Meryta, Munroidendron, Panax, Pentapanax, Polyscias, Pseudopanax, Reynoldsia, Sciadodendron, Tetra- plasandra, and their close allies), and the ''Eleutherococcus-Dendropanax-Schefflera group'' (including Brassaiopsis, Dendropanax, Eleutherococcus, Fatsia, Hedera, Oreopanax, Schefflera, Sinopanax, and their close allies). The ITS trees also permit a re-evaluation of several taxonomically important morphological characters (e.g., petal aestivation, leaf architecture, carpel number, and habit), and provide the opportunity to assess traditional generic delimitations in the family. Four of the largest genera appear to be either polyphyletic (Schefflera, Pseudopanax) or paraphyletic (Aralia, Polyscias), but further studies will be needed to fully re-define these complex taxa. Outgroup comparisons and the placement of Astrotricha and Osmoxylon (in basally-branching lineages in Araliaceae) help to confirm a paleotropical origin of the family. The ITS topologies suggest that biogeographic radiations into different tropical/subtropical regions and into the north and south temperate regions occurred early in the history of core Araliaceae. Temperate taxa have arisen several times indepen- dently from tropical and subtropical relatives, although a few subtropical taxa may be found nested within temperate clades (e.g., Pentapanax within Aralia). Migrations between the Old and New Worlds are also sug- gested for several taxa, including Aralia, Panax, Oplopanax, and the Sinopanax—Oreopanax generic pair.

Comparison of the flora and vegetation of the southern Andes and New Zealand

The annual range of temperatures in the southern Andes is similar to that in New Zealand, although they are cooler at comparable latitudes. South of 45°S in Chile the precipitation regime is also similar to New Zealand, but northwards and also east of the Andes there is an increasing period of Summer dryness. There are corresponding similarities in vegetation, especially in evergreen Nothofagus forests, tussock grassland in eastern rain shadows, and cushion bogs. Deciduous Nothofagus species are absent from New Zealand, but dominate widely in drier and colder environments of the southem Andes. In the southern Andes deciduous Nothofagus forms the subalpine forest and krummholz although, in the northern part of the region, there is also Araucaria araucarna growing as erect, emergent trees. Volcanic eruptions may lower the tree limit so that it intersects with evergreen Nothofagus forest. In New Zealand, evergreen Nothofagus species, which are less cold‐resistant than the deciduous Andean species, form most tree limits, and a belt dominated by tall Chionochloa tussocks intervenes between forest and low‐growing alpine vegetation. The absence of very hardy tree species in the New Zealand mountains may be related to isolation and late uplift. Extrapolation to tree limit indicates southern Andean warmest‐month mean temperatures from around 7°C in northern localities to only 5.7°C at 55°S, compared with 10°C which prevails in New Zealand. Since tree limit altitudes in the Southern Andes exceed those of New Zealand by at least 250 m, this indicates that in temperature terms New Zealand tree limits are 550 m lower than those of the southern Andes, corresponding with summer isotherms 3.3°C warmer. Vascular species were listed from equivalent vegetation types in the southern Andes and New Zealand, including forest, rain‐shadow grassland, alpine, coastal, swamp, lake‐edge and bog vegetation, and also from communities near the upper tree limit without close equivalents, notably deciduous forest in the Andes and Chionochloa grassland in New Zealand. Phytogeographic categories were assigned to all species, genera, and families. These were grouped as shared‐austral, shared with wider distributions, ‘’realm‐endemic‘’ confined to either south America or Australasia, and non‐shared with wider distributions About 90% of the 465 species listed from the southem Andes and 522 listed from New Zealand are realm‐endemics. Forty species or closely related pairs of species are shared, nearly half of these being coastal. Among genera, realm‐endemics are the largest element overall and exceed 30% in forests of both regions and in New Zealand subalpine, grassland, alpine, successional, and bog vegetation. Shared genera that extend to north temperate regions form the next most important, reaching over 40% in southern Andean swamp and New Zealand coastal samples. Shared genera with austral distributions reach 21–32% in all New Zealand vegetation classes and southern Andean bog, compared with 5–20% in other southern Andean vegetation classes. They contribute disproportionately to the physiognomic similarities between the two regions, notably in Nothofagus forests and bogs. Non‐shared genera with austral or subtropical distributions are most numerous in forest samples from each region. Non‐shared genera with north temperate distributions constitute only 2% in New Zealand, contrasting with the southern Andes where they constitute 19% overall and 20–29% in subalpine, grassland, alpine, successional, and coastal vegetation. Distribution of families among phytogeographic categories is similar to that of genera, except that more are shared‐widespread and fewer are shared‐austral and realm‐endemic. Sequencing of the gene rbcL for pairs of taxa in shared‐austral genera and for populations of Hebe salicfolia yields divergence estimates ranging from 130 ± 75 to 7 ± 4 million years. Divergences among tree species in shared genera may predate the separation of Australasia from Antarctica and South America, but not the separation of New Zealand from Australia. Taxa of open habitats show the most recent divergences, and their presence in both regions demands some mode of transoceanic dispersal. Possibly as late as the Pliocene, this may have involved a partly vegetated Antarctica.

Prevalence of fungal infections in adult Delia radicum and Delia floralis captured on the edge of a cabbage field

AbstractBrassiceye® traps baited with ethylisothiocyanate were modified and used to collect live adults of Delia radicum (L.) and Delia floralis (Fallén) (Diptera: Anthomyiidae) from the field to observe the prevalence of Entomophthora muscae (Cohn) Fresenius and Strongwellsea castrans Batko & Weiser. The traps were highly effective and selective for D. radicum and D. floralis. Of the flies identified, 98.4% in 1996 and 93.7% in 1997 were either D. radicum or D. floralis. In 1997 the maximum mean catch was as high as 82 flies per trap per day, and more than 80% of these were females.During both seasons E. muscae caused relatively high levels of mortality in adult populations of D. radicum and D. floralis. The fungus caused a total infection level of 17.9% in 1996 and 47.7% in 1997 with infection peaks of 82.4% in 1996 and 87.5% in 1997. Both years, a significant positive correlation was found between E. muscae prevalence and temperature. One infection peak was observed for S. castrans in 1996, and during that season the total S. castrans infection level was 18.0%. In 1997, the total S. castrans infection level was as low as 8.1%. There is no strong indication that the prevalence of E. muscae or S. castrans differs between either the fly species or sexes within species.

Richness and diversity of helminth communities in tropical freshwater fishes: empirical evidence

AbstractAimPublished information on the richness and diversity of helminth parasite communities in tropical freshwater fishes is reviewed in response to expectations of species‐rich parasite communities in tropical regions.LocationAreas covered include the tropics and some subtropical areas. In addition, the north temperate area of the nearctic zone is included for comparison.MethodsData from 159 communities in 118 species of tropical freshwater fish, summarized from 46 published studies, were used for this review. Parasite community descriptors used in the analyses included component community richness and calculated mean species richness. Data from 130 communities in 47 species of nearctic north temperate freshwater fish were summarized from 31 studies and used for comparison.ResultsThe component helminth communities of many tropical freshwater fish are species‐poor, and considerable proportions of fish from certain parts of the tropics, e.g. West African drainages, are uninfected or lightly infected. Mean helminth species richness was low and equaled or exceeded 2.0 in only 22 of 114 communities. No single group of helminths was identified as a dominant component of the fauna and species composition was variable among and within broader geographical areas. The richest enteric helminth assemblages were found in mochokid and clariid catfish with a mixed carnivorous diet, whereas algal feeders, herbivores and detritivores generally had species‐poor gut helminth communities. Comparisons indicated that certain areas in the north temperate region had higher helminth species richness in fishes than areas in the tropics.Main conclusionsExpectations of high species richness in helminth communities of tropical freshwater fishes are not fulfilled by the data. Direct comparisons of infracommunities and component communities in host species across widely separated phylogenetic and geographical lines are inappropriate. Examination of latitudinal differences in richness of monophyletic parasite groups or of compound communities may uncover patterns different from those found in this study. Richness of helminth communities may be ultimately determined not by the number of host species present but by the degree of divergence of host lineages and by their diversification modes. A phylogenetic framework for hosts and parasites will reveal if increased host species richness within host clades, when host speciation is accompanied by habitat or diet specialization, or both, leads to lower helminth diversity in host species by fragmentation of a core helminth fauna characteristic or specific of the larger host clade. This pattern may be analysed in the context of cospeciation and acquisition from other unrelated hosts (host‐sharing or host‐switching).

Latitudinal patterns in the size distribution and seasonal dynamics of new world, freshwater cladocerans

Analysis of zooplankton communities in over 1,100 water bodies spanning the Western Hemisphere (77°S, 81°N latitude) revealed latitudinal patterns in cladoceran body size and Daphnia seasonal dynamics. The mean body length of cladoceran species occurring at different latitudinal intervals was greatest in north temperate regions, declining in size toward the poles and equator. Thus, mean cladoceran size was greatest in regions where the mean annual surface temperatures of lakes ranged from 6 to 8°C in both the Northern and Southern Hemispheres. The date of maximum Daphnia abundance and the period of minimum Daphnia abundance in lakes of North America was positively, linearly related to the latitudinal position of the lakes. The date of maximum abundance increased with latitude such that Daphnia peaked during nearly all months of the year depending on latitude, but usually within the same, narrow temperature range (15–20°C). The period of minimum Daphnia abundance decreased linearly with latitude such that abundance generally was minimal when water temperatures exceeded 20°C.

Cochlearia cochlearioides (Brassicaceae) Is a Rorippa

The Indian endemic Cochlearia cochlearioides, initially described as an Alyssum, is transferred to Rorippa, and the new combination R. cochlearioides (Roth) Al-Shehbaz & Jonsell is proposed. Rorippa cochlearioides (Roth) Al-Shehbaz & Jonsell is endemic to India. It has been known under different names in Cochlearia L. and first appeared as C. flava in Roxburgh (1814), but that name remained a nomen nudum until it was validated by Hooker (1852). The species was validly published by Roth (1821) as Alyssum cochlearioides, a legitimate name that was placed in synonymy of the later published and illegitimate C. alyssoides (De Candolle, 1824). Alyssum cochlearioides was then transferred to the monotypic Trochiscus by Schulz (1933) and to Cochlearia by Maheshwari (1957), but it is evident that neither of these generic assignments is appropriate. Perhaps the main reason that Rorippa cochlearioides has been kept for so long in Cochlearia is that it has globose, many-seeded fruits. However, such fruits are found in several species of Rorippa Scopoli, including the Asian R. globosa (Turczaninow ex Fischer & C. A. Meyer) Hayek, the North American R. calycina (Engelmann) Rydberg, R. columbiae (Suksdorf ex Robinson) Suksdorf ex T. J. Howell, R. sphaerocarpa (A. Gray) Britton, and R. subumbellata Rollins, and the eastern Asian-North American R. barbariifolia (DC.) Kitagawa (Jonsell, 1971, 1973; Rollins, 1993). Plants of Rorippa cochlearioides grow in lowland, tropical and subtropical areas of India and are restricted to the Gujarat and Gangetic Plains (Bhaumik, 1993). The species has pinnatifid, nonfleshy, auriculate cauline leaves, yellow flowers, spreading floral parts, terete fruits, obscurely veined thin valves, and up to 80 reddish, reticulate seeds per fruit. This combination of characters is found in many species of Rorippa and does not occur in any species of Cochlearia. Species of Cochlearia are distributed in the arctic, subarctic, and northern latitudes of the north temperate region, and they have more or less fleshy, entire to dentate nonauriculate leaves, white flowers, erect petals and stamens, somewhat narrowly septate fruits, prominently 1-veined thick valves, and often few to several, often tuberculate seeds per fruit. In fact, all the Himalayan species previously assigned to Cochlearia have been or should be transferred to other genera. It is interesting to note that Schulz (1936) placed Rorippa cochlearioides (as Trochiscus) in the tribe Drabeae, a tribe that he separated from the Arabideae primarily on the basis of silicles versus siliques, although he indicated that Nasturtium R. Brown (including Rorippa) is an exception in the Arabideae because it often has silicles. By contrast, Bhaumik (1993) placed the species (as C. cochlearioides) in the Lepidieae, where Cochlearia has been traditionally placed. In our opinion, neither of these tribal dispositions of Rorippa cochlearioides reflects its phylogenetic relationships, and the species should be placed in the same tribe as Rorippa and Nasturtium. To accommodate the species in Rorippa, the following new combination is proposed. Rorippa cochlearioides (Roth) Al-Shehbaz & Jonsell, comb. nov. Basionym: Alyssum cochlearioides Roth, Nov. P1. Sp. 322. 1821. TYPE: India. Benjamin Heyne s.n. (holotype, B-W).

Phylogenetic Relationships and the Evolution of Ovary Position in Saxifraga section Micranthes

Section Micranthes of the genus Saxifraga (Saxifragaceae) comprises 67 species that are distrib- uted throughout the northern hemisphere. A previous phylogenetic analysis indicates that this section is a lineage distinct from the remainder of Saxifraga. Recent taxonomic treatments have divided section Micranthes into four subsections: Cuneifoliatae, Micranthes, Rotundifoliatae, and Stellares. To investigate the phylogenetic relationships among species in section Micranthes and to test the monophyly of each of the four subsections, we sequenced the chloroplast gene matK for 26 species of section Micranthes. The results of our parsimony analyses suggest that subsections Micranthes and Stellares are each monophyletic. The single taxon of subsec- tion Cuneifoliatae (S. calycina) for which material could be obtained appears within a clade representing sub- section Rotundifoliatae; hence Cuneifoliatae may not be distinct from Rotundifoliatae. Within section Micranthes there exists a high diversity of ovary positions, ranging from what has been described as fully superior to greater than one-half inferior. Examination of this character in light of our matK strict consensus tree indicates that the major trend in gynoecial evolution in section Micranthes has been from an ancestor with what has been termed a superior ovary towards greater inferiority. However, gynoecial evolution in subsection Mi- cranthes is complex, with several apparent reversals towards greater superiority. The genus Saxifraga, as traditionally defined, con- sists of approximately 440 species and is the largest genus in Saxifragaceae s. s. (Webb and Gomall 1989). Saxifraga is distributed throughout the north temperate and Arctic regions, with centers of di- versity in the mountains of Europe, eastern Asia, and western North America. The genus is extreme- ly diverse in morphology, ecology, habit, and cy- tology, which has led to difficulty in defining its limits. For example, Haworth (1812) divided Saxi- fraga into 16 segregate genera (see also Small and Rydberg 1905; Love 1983). However, many inves- tigators prefer a broad interpretation of Saxifraga (e.g., Engler 1872; Engler and Irmscher 1916; Gor- nall 1987; Webb and Gornall 1989). Recent phylo- genetic analyses of cpDNA restriction sites (Soltis et al. 1993), rbcL and matK sequences (Johnson and Soltis 1994, 1995; Soltis et al. 1996), and ITS se- quences (Johnson and Soltis 1998) indicate clearly that Saxifraga is polyphyletic, with species forming two distinct clades-Saxifraga s. s. and Micranthes. The former comprises most of the 15 sections tra- ditionally placed in Saxifraga, whereas the Micran- thes clade includes Saxifraga section Micranthes (67 species). The closest relatives of the Micranthes clade appear to be Saxifraga section Merkianae (two spe- cies), and the monotypic Cascadia (= S. nuttallii). Based primarily on features of the seed coat (Kaplin 1981), Webb and Gornall (1989) recognized four subsections within section Micranthes: Micran-

Impact of El Chichon and Pinatubo on ozonesonde profiles in north extratropics

The impact of El Chichon and Pinatubo volcanic eruptions on ozonesonde‐derived ozone values in 8–16, 16–24 and 24–32 km layers is estimated for north polar and temperate zones, and the north temperate regions of North America, Europe and Asia, by minimizing the influence of solar cycle and trend, and adjusting for the quasi‐biennial variation in ozone by use of the superposed epoch method. Based on this procedure, in north temperate 8–16 and 16–24 km layers the impact of El Chichon is a significant 10% ozone decrease 3–4 seasons after eruption, the impact of Pinatubo a significant 15% ozone decrease 7 seasons after eruption. In the 24–32 km layer the respective ozone decreases are 2% and 5%, the latter significant. In the north polar zone the ozone decreases following Pinatubo are a significant 20% and 10% in 8–16 and 16–24 km layers, but there are marginally significant ozone increases of 5% in the 24–32 km layer following both eruptions.

Monitoring warm‐water fish populations in north temperate regions: sampling considerations when using proportional stock density

AbstractThree lakes were repeatedly sampled at night using boat electric fishing, experimental gill netting, and fyke netting from May to November 1993 to evaluate the feasibility of using proportional stock density (PSD) to monitor warm‐water fish populations in Washington State, USA. Additionally, average night‐time boat electric fishing catch‐per‐effort of largemouth bass, Micropterus salmoides (Lacepéde), from 30 Washington lakes was also analysed to determine the amount of effort required to obtain adequate samples for precise PSD estimates. Temporal variations in PSD were not large enough to affect the management of warm‐water fish populations in the small Washington lakes studied. However, the considerable effort required to obtain precise PSD estimates may limit its usefulness for warm‐water fisheries surveys in the Pacific Northwest. On average, from three to 13 nights of electric fishing effort are needed to capture enough stock‐length largemouth bass for PSD estimates, depending on the precision desired (80–95%) and the location of the lake (eastern or western Washington). Catch of stock‐length fish can be maximized by using electric fishing for centrarchids and gill netting for yellow perch, Perca flavescens (Mitchill), in June or September. Adequate samples for precise PSD estimates can be difficult to obtain from Pacific Northwestern lakes, even when using recommended gear at optimum sampling times. Inability to capture an adequate sample size for precise PSD estimates may be responsible for some of the fluctuation in PSDs in some studies of warm‐water fish populations in northern areas. Managers in other northern climates may find that low sample size may account for large variations in PSDs reported.

Activity Budget of White-Faced Whistling-Ducks during Winter and Spring in Northern Kwazulu-Natal, South Africa

Despite the fact that white-faced whistling-ducks (Dendrocygna viduata) incur the added costs of flight-feather replacement on wintering areas, little is known about how they allocate their time and energy during this period. We used focal sampling techniques to quantify diel activity patterns of nonbreeding white-faced whistling-ducks using semipermanent pans in northern KwaZulu-Natal, South Africa, during the winter and spring of 1995. A large proportion of early winter (44% of diel activities), late winter (29%), and spring (50%) activities were attributed to foraging. Increased foraging intensity during early winter and spring (P < 0.05) corresponded with peak flight-feather replacement. Birds spent more time in comfort-related activities (sleep, loaf, preen) during late winter (57%) than both early winter (35%) and spring (29%; P < 0.05). Time spent in locomotion (walk, swim, fly) decreased as winter progressed and was lowest during spring, whereas alert behaviors and aggression increased (P < 0.05). No courtship activities were observed. Activities of white-faced whistling-ducks were correlated more strongly with flock size and ambient temperature than several other climatic variables. Relative to waterfowl wintering in north-temperate regions, the activity patterns of white-faced whistling-ducks were probably influenced by either or both the nutrient costs of feather replacement and a reduction in foraging opportunities during the flightless period, as well as a low availability of cereal grains near wintering areas. Fifty-three percent of foraging activities occurred nocturnally, which further ex-emplifies the importance of considering nocturnal behaviors when assessing the activity patterns and energetics of waterfowl.

The identification of flowering plant families: including a key to those native and cultivated in north temperate regions

The identification of flowering plant families: including a key to those native and cultivated in north temperate regions