A Lost Link between a Flightless Parrot and a Parasitic Plant and the Potential Role of Coprolites in Conservation Paleobiology

Late Quaternary extinctions and population fragmentations have severely disrupted animal‐plant interactions globally. Detection of disrupted interactions often relies on anachronistic plant characteristics, such as spines in the absence of large herbivores or large fruit without dispersers. However, obvious anachronisms are relatively uncommon, and it can be difficult to prove a direct link between the anachronism and a particular faunal taxon. Analysis of coprolites (fossil feces) provides a novel way of exposing lost interactions between animals (depositors) and consumed organisms. We analyzed ancient DNA to show that a coprolite from the South Island of New Zealand was deposited by the rare and threatened kakapo (Strigops habroptilus), a large, nocturnal, flightless parrot. When we analyzed the pollen and spore content of the coprolite, we found pollen from the cryptic root‐parasite Dactylanthus taylorii. The relatively high abundance (8.9% of total pollen and spores) of this zoophilous pollen type in the coprolite supports the hypothesis of a former direct feeding interaction between kakapo and D. taylorii. The ranges of both species have contracted substantially since human settlement, and their present distributions no longer overlap. Currently, the lesser short‐tailed bat (Mystacina tuberculata) is the only known native pollinator of D. taylorii, but our finding raises the possibility that birds, and other small fauna, could have once fed on and pollinated the plant. If confirmed, through experimental work and observations, this finding may inform conservation of the plant. For example, it may be possible to translocate D. taylorii to predator‐free offshore islands that lack bats but have thriving populations of endemic nectar‐feeding birds. The study of coprolites of rare or extinct taxonomic groups provides a unique way forward to expand existing knowledge of lost plant and animal interactions and to identify pollination and dispersal syndromes. This approach of linking paleobiology with neoecology offers significant untapped potential to help inform conservation and restoration plans. Un Eslabón Perdido entre un Loro No Volador y una Planta Parásita y el Papel Potencial de Coprolitos en Paleobiología de la Conservación     

IMPACT OF IRRIGATION WELLS ON BASEFLOW OF THE BIG BLUE RWER,NEBRASKA1

ABSTRACT: The Kansas-Nebraska Big Blue River compact requires that the state of Nebraska insure a minimum flow of the Big Blue River across the state line. There are two options that the state of Nebraska may use to ensure minimum flows. The obvious option is to limit surface-water irrigators along the river. However, under the terms of the compact, a second option may be to regulate irrigation wells that are within one mile of the river and were installed after November 1, 1968. The objective of this study is to quantify the effects of 17 irrigation wells that may be regulated on baseflow of the Big Blue River. A finite-element model is used to study the hydrogeologic system between DeWitt and Beatrice, Nebraska. The 17 wells that may be regulated are located between these towns and are developed in sediments deposited in a cross-cutting paleovalley anchor alluvium associated with the Big Blue River. While there wore considerable existing data, additional data were gathered by drilling an additional nine test holes, conducting several aquifer tests, stream-stage measurements, and baseflow calculation through extensive stream-discharge measurements, establishment of a ground water-level monitoring network, determining the amount of water pumped for irrigation and municipal use in the area, and a short-term precipitation network. The model was calibrated using observed baseflow and ground water level data. The model clearly shows that regulating the 17 wells to maintain baseflow would have a minimal effect on the overall water budget. This is reasonable, especially considering that there are over 250 irrigation wells in the project area. The 17 wells considered pumped only 6 percent of the total pumpage within the modeled area during the irrigation season of 1984. The computer model provides the documentation needed to demonstrate this fact. Although much of the resources spent and a significant amount of hydrogeologic data are being collected over a period of three years on a relatively small area, the simulation model could be improved through further field testing of the aquifer and stream-bed sediment characteristics and quantification of ground water recharge, discharge, and evapotranspiration rates.     

Heavy Metals in Organs and Tissues of the European Black Vulture (Aegypius monachus): Dependence on Living Conditions

The distribution of Fe, Zn, Cu, Cd, Mn, Pb, and Ni in the organs and tissues (kidneys, liver, lungs, brain, heart, muscles, and feathers) of the European black vulture (Aegypius monachus) was studied. It was shown that heavy metals were not responsible for the mass mortality of these birds in southern Primorye in the winter of 2001–2002. The level of pollution with heavy metals of the range of European black vultures wintering in this region (northern China and western Mongolia) may be regarded as insignificant.     

羌塘高原人与野生动物冲突的成因

随着自然保护事业的发展,人与野生动物冲突加剧成为自然保护与地区发展面临的新问题。但人与野生动物冲突研究具有多主体性、复杂性和跨学科性,研究难度大。本文以羌塘高原为例,采用人与野生动物相互作用社会生态系统的概念,梳理了人与野生动物冲突主体的规模、分布,识别了食草野生动物与家畜争食牧草、人类聚落与野生动物竞争生存空间、草场围栏分隔栖息地及阻断迁徙通道等三种主要冲突类型。考虑草畜兽平衡核算了草地承载状况,模拟了家畜与野生动物生存空间重叠,刻画了草场围栏对栖息地及迁徙通道的影响。从重叠空间的资源竞争及人类活动扰动等方面剖析了人与野生动物冲突成因。可为厘清冲突机制,提高干预效果提供新认知。     

Prey vulnerability in relation to sexual coloration of prey

Sexual selection that results in the evolution of exaggerated secondary sexual characters has been hypothesized to impose production and maintenance costs of such traits on their bearers. Costs arising from sexual selection could increase the intensity of predator-mediated natural selection, leading to the prediction that species with exaggerated secondary sexual characters should be particularly susceptible to predation. We tested this prediction in a comparative analysis based on 31,745 prey individuals belonging to 66 species of birds collected from a total of 937 breeding events by 33 to 66 different pairs of European sparrowhawks Accipiter nisus annually during a period of 21 years. To assess vulnerability of different species we estimated a prey vulnerability index based on the difference in the logarithmically transformed absolute abundance of prey minus the logarithmically transformed expected abundance as determined by population density of breeding birds. The prey vulnerability index was predicted by sexual dichromatism, accounting for 23% of the variance in risk of predation among species, even when considering similarity in phenotype among species due to common descent (in the latter case explaining 12% of the variance). This finding suggests that sexual selection is an important evolutionary force-affecting predator–prey interactions.Electronic Supplementary Material Supplementary material is available for this article at     

Prey odor discrimination by ingestively naive coachwhip snakes(Masticophis flagellum)

Summary Ingestively naive hatchling coachwhip snakes(Masticophis flagellum) detected integumentary chemicals from several potential prey species and discriminated them from chemical stimuli from other animals and from distilled water, strongly suggesting a genetic basis for these abilities. The strongest responses were to lizard and snake stimuli, which form a major part of the diet. Variable responses to chemical cues from other taxa are discussed. Responses by coachwhip snakes to prey chemicals appear to be highly specific, as suggested by the stronger reaction to vomodors of sympatric than of allopatric lizard species. The highly developed use of chemical cues by the diurnal, visually oriented coachwhip snake emphasizes the general importance of chemical senses to predation by nonvenomous snakes, regardless of the involvement of vision.     

The iridoid glycoside,catalpol, as a deterrent to the predatorCamponotus floridanus (Formicidae)

Summary We investigated the role of the iridoid glycoside, catalpol, as a deterrent to the predator,Camponotus floridanus. Four laboratory colonies of this ant were offered buckeye caterpillars (Junonia coenia: Nymphalidae) raised on diets with and without catalpol. The same colonies were offered sugar-water solutions containing varying concentrations of catalpol, in both no-choice and choice tests. Regardless of diet, buckeye caterpillars appeared to be morphologically protected from predation by the ants, possibly because of their large spines or tough cuticle. However, buckeyes raised on diets with catalpol had high concentrations of catalpol in their hemolymph; extracts of this high-catalpol hemolymph proved to be an effective deterrent to the ants. When starved ants were not given the choice of food items, they were more likely to consume sucrose solutions that contained 5 mg catalpol/ml or 10 mg catalpol/ml than they were to consume solutions with 20 mg catalpol/ml. When they were given a choice of sugar solution or a sugar solution containing catalpol, the ants avoided solutions with catalpol at any of these concentrations. Ant colony responses to catalpol in sucrose solutions varied considerably over time and among colonies.     

Two herbivore-deterrent iridoid glycosides reduce the in-vitro growth of a specialist but not of a generalist pathogenic fungus of Plantago lanceolata L

Summary. Many secondary plant compounds are involved in defense against both insect herbivores and pathogens. Two secondary plant compounds of Plantago lanceolata, the iridoid glycosides catalpol and its precursor aucubin, are well known for their deterrent effects on generalist and non-adapted specialist insect herbivores. We tested the effects of these compounds on the in-vitro growth of a specialist and generalist fungal pathogen of this host species. Two chemical forms of these iridoids were tested. The glycosides and their aglycones, the products of enzymatic conversion by specific $/Beta$-glucosidase enzymes. The glycosides enhanced growth of both the specialist fungus Diaporthe adunca and the generalist fungus Fusarium moniliforme var. subglutinans. The positive effect of these glycosides on the generalist fungus is in sharp contrast with the generally negative effects of these glysosides on generalist insect herbivores. The aglycones of aucubin and catalpol reduced the growth of the specialist fungus D. adunca, but, contrary to expectation, enhanced the growth of the generalist fungus F. moniliforme var. subglutinans. Effects of aucubin on D. adunca were stronger than effects of catalpol. This was true both for the growth stimulating effects of the glycosides and for the fungitoxic effects of the aglycones. We therefore expect that the effects of these iridoids in P. lanceolata on the specialist fungus will strongly depend on the ratio between catalpol and its precursor aucubin and the chemical form (glycoside or aglycone) in which these compounds are encountered by the fungus during growth. Our results suggest that iridoid glycosides in P. lanceolata can be used as defense against both herbivores and pathogens, but that their effects are highly specific with respect to the natural enemy species that is encountered. Received 11 April 2002; accepted 9 August 2002     

Residues of Organochlorinated Pesticides in Eggs of Water Birds from Tai Lake in China

The levels of organochlorine compounds in eggs of water birds from the colony on Tai Lake in China were studied. The eggs were collected in 2000 and belonged to the following species: 65 samples of black-crowned night heron (Nycticorax nycticorax), 36 samples of little egret (Egretta garzetta), 26 samples of cattle egret (Bubulcus ibis) from 13 clutches and 43 samples of Chinese pond heron (Ardeola bacchus) from 17 clutches. Dichlorodiphenyltrichloroethane (DDT) and its derivates (DDE and DDD), hexachlorocyclohexane (HCH) and its isomers (-HCH, -HCH, -HCH, -HCH), heptachlor, heptachlor epoxide, aldrin, dieldrin, endrin, endrin aldehyde, -endosulfan, -endosulfan, and endosulfan sulfate were determined in the laboratory by gas chromatography. The data showed that DDE had the highest levels in all the samples, followed by -HCH. The mean levels of DDE among the water bird species were in the order as follows: black-crowned night heron (5464.26ng/g, dry weight) > Chinese pond heron (2791.12ng/g, dry weight) > little egret (1979.97ng/g, dry weight) > cattle egret (660.11ng/g, dry weight). DDT and its metabolites accounted for 90% of the total organochlorines, except that it was only 73% for cattle egret. The differences of the residue among the bird species were statistically significant and could be attributed to their variations in prey and habitat. Although the DDE burdens in Tai Lake were much lower than 8 g/g (wet weight) which are thought to have significant adverse effects on black-crowned night herons, they would be expected to increase the risk of adverse effects on survival of chicks of herons and egrets, particularly black-crowned night heron, based on the critical value of 1 g/g (wet weight) DDE. The burdens of HCHs in this study were higher and the cyclodienes were lower than those found elsewhere.     

Effect of queen quality on interactions between workers and dueling queens in honeybee (Apis mellifera L.) colonies

The fitness of a social insect colony depends greatly on the quality (i.e., mating ability, fecundity, and offspring viability) of its queen(s). In honeybees, there is marked variation in the quality of young queens that compete in a series of lethal duels to replace a colonys previous queen. Workers interact with queens during these duels and could increase their inclusive fitness by biasing the outcomes of the duels in favor of high-quality queens. We predicted that workers will have more antagonistic interactions (chasing, grabbing, clamping) and fewer beneficent interactions (feeding, grooming) with low-quality than high-quality queens. To test this prediction, we reared queens from 0-day-old, 2-day-old, and 3-day-old worker larvae in observation colonies undergoing queen replacement, thus producing high-quality, low-quality, and very low-quality queens, respectively. Immediately after each queen emerged, we observed her for 1 h to record her interactions with the workers. Subsequent morphological measurement of the queens confirmed that initial larval age had a significant effect on queen quality. However, there was no consistent effect of queen quality on the rates of worker–queen interactions, thus falsifying our hypothesis. The mean power of our tests was high (0.599), therefore the probability of a type II error (a false negative) is low. We conclude that if workers actively select high-quality queens, then they do so prior to queen duels, during queen development. We suggest that each worker–queen interaction has a distinct adaptive significance rather than forming a suite of behavior that favors particular queens (e.g., chasing repels any queen that approaches a queen cell, thus protecting all queen cells from destruction).Communicated by M. Giurfa