MONITORING POPULATION LEVELS OF EIGHT SPECIES OF NOCTUIDS WITH SEX-ATTRACTANT TRAPS IN SOUTHERN ALBERTA, 1978–1983: CONGRUENCY OF YEAR-TO-YEAR FLUCTUATIONS IN INTRASPECIFIC DENSITY SHOWN BY SUBSETS OF MONITORING SITES

AbstractThe abundance levels of eight species of cutworms and army worms were monitored with sex-attractant traps at 81 locations in a 13 000-km2 area of southern Alberta from 1978 to 1983. Year-to-year change in population levels could be consistently detected by monitoring at a relatively small number of locations. For all species, subsets of selected locations along transects, or random subsets of as few as five locations, showed year-to-year fluctuations in mean catch per trap that were similar in pattern to those of the whole monitored area. The results indicate that long-term surveillance monitoring of pest species of cutworms and armyworms to detect year-to-year population changes, and long-term trends, is feasible in terms of both the resource requirements and reliability of the relative population estimates.

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Long-term and large-scale multispecies dataset tracking population changes of common European breeding birds

Scientific Data ◽

10.1038/s41597-021-00804-2 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Vojtěch Brlík ◽

Eva Šilarová ◽

Jana Škorpilová ◽

Hany Alonso ◽

Marc Anton ◽

...

Keyword(s):

Population Size ◽

Large Scale ◽

Breeding Birds ◽

Population Changes ◽

Size Change ◽

Relative Population ◽

Bird Monitoring ◽

Population Size Change ◽

Country Specific

AbstractAround fifteen thousand fieldworkers annually count breeding birds using standardized protocols in 28 European countries. The observations are collected by using country-specific and standardized protocols, validated, summarized and finally used for the production of continent-wide annual and long-term indices of population size changes of 170 species. Here, we present the database and provide a detailed summary of the methodology used for fieldwork and calculation of the relative population size change estimates. We also provide a brief overview of how the data are used in research, conservation and policy. We believe this unique database, based on decades of bird monitoring alongside the comprehensive summary of its methodology, will facilitate and encourage further use of the Pan-European Common Bird Monitoring Scheme results.

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Intakes as Sampling Locations for Investigating Long-Term Trends in Zooplankton Populations

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f84-186 ◽

1984 ◽

Vol 41 (10) ◽

pp. 1513-1518 ◽

Cited By ~ 2

Author(s):

Marlene S. Evans ◽

Loren E. Flath

Keyword(s):

Community Structure ◽

Power Plant ◽

Lake Michigan ◽

Population Estimates ◽

Sampling Location ◽

Water Interface ◽

Accurate Representation ◽

Sampling Locations ◽

Long Term Trends

We present data demonstrating the representativeness of a power plant intake as a sampling location for investigating long-term trends in zooplankton populations. The intake (Donald C. Cook Nuclear Plant) and the inshore region (southeastern Lake Michigan) were sampled within a matter of days on 54 occasions between April 1975 and November 1981. Intake population estimates were significantly correlated with inshore region population estimates for all 26 zooplankton taxa categories analyzed. Differences in abundances in intake and inshore region samples were not significant for most euplanktonic taxa. The plant apparently entrained water and microcrustaceans from the sediment–water interface. However, because vertically hauled plankton nets do not effectively sample the lower 1 m of the water column, intake sampling may provide a more accurate representation of nearshore region copepod and cladoceran community structure than traditionally employed methods for inshore region sampling.

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MONITORING POPULATION LEVELS OF EIGHT SPECIES OF NOCTUIDS WITH SEX-ATTRACTANT TRAPS IN SOUTHERN ALBERTA, 1978–1983: CONSISTENCY OF TRAP CATCHES AND PRECISION OF POPULATION ESTIMATES

The Canadian Entomologist ◽

10.4039/ent119557-6 ◽

1987 ◽

Vol 119 (6) ◽

pp. 557-566 ◽

Cited By ~ 1

Author(s):

J.R. Byers ◽

D.L. Struble ◽

G.B. Schaalje

Keyword(s):

Sex Attractant ◽

Late Summer ◽

Population Level ◽

Weather Conditions ◽

Early Summer ◽

Flight Period ◽

Relative Population ◽

Peridroma Saucia ◽

Southern Alberta ◽

Trap Catches

AbstractSex-attractant traps were used to monitor the relative abundances of eight species of cutworm and army worm moths at 81 locations in a 13 000-km2 (5000-mi2) area of southern Alberta from 1978 to 1983. Clover cutworm (Discestra trifolii (Hufn.)), variegated cutworm (Peridroma saucia (Hbn.)), bertha armyworm (Mamestra configurata Wlk.), and Leucania commoides Gn. were monitored during spring and early summer, and redbacked cutworm (Euxoa ochrogaster (Gn.)), darksided cutworm (Euxoa messoria (Harr.)), pale western cutworm (Agrotis orthogonia Morr.), and army cutworm (Euxoa auxiliaris (Grt.)) during late summer and fall.The ranking of moth catches among locations within years was highly consistent, indicating that the spatial pattern of abundance within the survey area remained stable during each flight period. The corollary is that differences in population levels among locations were being consistently detected. Most of the species also exhibited a considerable degree of consistency of pattern of abundance between consecutive years and to some extent over all years.Estimates of the variability associated with individual traps, between duplicate traps, and among locations were obtained for each species. The within-location variability was always much less than the among-location variability, indicating that a meaningful measure of the relative population level at each location was being obtained. When abundance levels approached economic thresholds the likelihood of moth catches in duplicate traps being within 20% of the mean catch for a location was usually greater than 80%. Year-to-year differences in mean trap catches were frequently significant at the 95% confidence level and the monitoring system could detect relatively small changes in population level between years. Season cumulative trap catches are a composite measure of abundance and the mate-searching activity of males. Weather conditions that restrict male activity are also likely to reduce oviposition by females. Cumulative trap catches may therefore be closely correlated with realized fecundity.

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Distribution Patterns of Grasshoppers and Their Kin over the Eurasian Steppes

Insects ◽

10.3390/insects12010077 ◽

2021 ◽

Vol 12 (1) ◽

pp. 77

Author(s):

Michael G. Sergeev

Keyword(s):

Population Distribution ◽

Locusta Migratoria ◽

Distribution Patterns ◽

General Distribution ◽

Population Changes ◽

Great Abundance ◽

Warm Summer ◽

Long Term Trends ◽

Dociostaurus Maroccanus

The main aims of this paper are to reveal general patterns of Orthoptera distribution in the Eurasian steppes, to evaluate long-term trends of changes in distribution of taxa and populations, and to estimate the potential for population changes relative to human activity and global warming trends. The main publications concerning diversity and distribution of these insects over the steppes are analyzed. The fauna of the Eurasian steppes includes more than 440 species of Orthoptera. The general distribution of grasshoppers and their kin in the Eurasian steppes reflects their common associations with different grasslands. The species richness increases from the relatively cold forest-steppes to the semi-deserts with their warm summer. There are some endemic or subendemic taxa, including the tribe Onconotini (Tettigoniidae). The populations’ distribution of Orthoptera is also analyzed. The populations of native Orthoptera extend through all the herbaceous landscapes. Under these conditions, the interrelating of colonies of each species may result in great abundance. The population distribution of three species locusts (Locusta migratoria, Calliptamus italicus, Dociostaurus maroccanus) is also discussed. Some notable changes of their populations’ distribution and dynamics are characterized. The situation with rare Orthoptera is estimated. Retrospective and prospective of the steppe fauna of Orthoptera are discussed.

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Hatching phenology is lagging behind an advancing snowmelt pattern in a high-alpine bird

Scientific Reports ◽

10.1038/s41598-021-01497-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Christian Schano ◽

Carole Niffenegger ◽

Tobias Jonas ◽

Fränzi Korner-Nievergelt

Keyword(s):

Reproductive Period ◽

Population Declines ◽

Resource Abundance ◽

Resource Requirements ◽

Underlying Causes ◽

Long Term Trends ◽

Adaptive Phenotypic Plasticity ◽

Hatching Phenology ◽

Alpine Environments

AbstractTo track peaks in resource abundance, temperate-zone animals use predictive environmental cues to rear their offspring when conditions are most favourable. However, climate change threatens the reliability of such cues when an animal and its resource respond differently to a changing environment. This is especially problematic in alpine environments, where climate warming exceeds the Holarctic trend and may thus lead to rapid asynchrony between peaks in resource abundance and periods of increased resource requirements such as reproductive period of high-alpine specialists. We therefore investigated interannual variation and long-term trends in the breeding phenology of a high-alpine specialist, the white-winged snowfinch, Montifringilla nivalis, using a 20-year dataset from Switzerland. We found that two thirds of broods hatched during snowmelt. Hatching dates positively correlated with April and May precipitation, but changes in mean hatching dates did not coincide with earlier snowmelt in recent years. Our results offer a potential explanation for recently observed population declines already recognisable at lower elevations. We discuss non-adaptive phenotypic plasticity as a potential cause for the asynchrony between changes in snowmelt and hatching dates of snowfinches, but the underlying causes are subject to further research.

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