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Lepidoptera of North America

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https://hdl.handle.net/10217/195581

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Browsing Lepidoptera of North America by Author "Chu, Janet, author"

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    Lepidoptera of North America 12. Butterflies - 2018 inventories in nine Boulder County open spaces
    (Colorado State University. Libraries, 2018) Chu, Janet, author; C.P. Gillette Museum of Arthropod Diversity, publisher
    This was the fifteenth year butterflies were inventoried on nine select properties within Boulder County Parks and Open Space (BCPOS) lands. The trend for all butterfly species was determined for all surveyed Open Spaces and shows a downward trend of approximately -1.3 Individuals per Research Hour per Year. This trend (R2=0.4) explains 40% of the variation for years 2004 through 2018 which is a decrease of almost 3% /year. This leads to the conclusion that the butterfly population will be significantly diminished over time under present conditions. Our results indicate that most butterfly species are not reproducing successfully enough to keep their population numbers stable within Boulder County. Cabbage Whites (Pieris rapae) and Aphrodite Fritillaries (Speyeria aphrodite) were the most numerous of individual butterflies while Field Crescents (Phyciodes pulchella) represented the widest distribution flying in each of the Open Spaces. These resident butterflies are indicator species, as they are primary for determining if the environment is remaining vital. Of course, the BCPOS properties are influenced by state-wide and national environmental changes. Fourteen volunteers were in the field 70 days completing 175 hours of Research Hours (RH) in 2018 recording data and taking photographs. Often team members hiked somewhat near each member to observe, then experienced members input their sightings into the single day's data. The season's cumulative volunteer hours totaled 500. Of course, those following a transect were usually hiking alone, their numbers available separately, but in 2018 these were counted within the seasonal data.
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    Lepidoptera of North America 17. 2019 butterfly inventories within Boulder County open spaces, Boulder, Colorado
    (Colorado State University. Libraries, 2020-03) Chu, Janet, author; C.P. Gillette Museum of Arthropod Diversity, publisher
    Butterfly Inventories took place for the 16th consecutive year within Boulder County Open Space properties. Over the years 2004-2019, 129 butterfly species have been sighted in eight of the Open Spaces; 76 were counted in this year alone. More photographers than ever before on the team this season captured nearly 93 of the known 202 butterflies in Boulder County. These Butterfly Research Volunteers helped collect data during 340 field hours. Venice Kelly studying on Sherwood Road and in the main Caribou Ranch contributed at least 53 hours on site. Other volunteers did not complete the past transects due to several reasons: trail being moved in the mid-season to a newer, grassier area from Geer Watershed, Heil Valley Ranch; unsafe high-speed bicycle interactions on the Loop Trail, Walker Ranch; personal reasons on Anne U. White Trail. Late wet, cold spring weather slowed butterfly emergences, resulting in some normally typically spring species flying with the early summer species. Certain summer species flew later into the early fall. August and September were mostly hot and dry allowing the continued flight by many brush-foot (Nymphalidae) butterflies.
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    Lepidoptera of North America 18. 2021 butterfly inventories within Boulder County open spaces, Boulder, Colorado
    (Colorado State University. Libraries, 2022-04-04) Chu, Janet, author; Hirschfeld, Sue, author; Kelly, Venice, author; C.P. Gillette Museum of Arthropod Diversity, publisher
    The butterfly inventories continued for the 18th year in a few of the Boulder County Open Space properties. However, because of the Calwood Fire during October 17, 2020, two of the survey areas were inaccessible; Plumely Canyon and the work road through the streamlet near the Lichen Trail. Geer Watershed had been burned, but the meadows above the Resident Ranger's Cabin and associated streamlets were made accessible with our 2021 permit. Cabbage Whites (Pieris rapae), Orange Sulphurs (Colias eurytheme) and Common Wood-nymphs (Cercyonis pegala) were more numerous when compared to 2015-2020 populations before the burn. In 2021 within other Open Spaces, Anne U. White and Caribou, the resident species produced noticeably large populations: Julia Orangetips (Anthocharis julia), Pine Whites (Neophasia menapia), Northern Checkerspots (Chlosyne palla), Common Wood-nymphs, Small Wood-nymphs (C. oetus), Common Checkered-skippers (Burnsius communis). On the other hand, the well adapted non- native Cabbage Whites were again the most common during the long season; Variegated Fritillaries (Euptoieta claudia) and Dainty Sulphurs (Nathalis iole) were numerous flying in from colonies in the eastern plains and low foothills where their host plants were plentiful. 95 species were seen in 2021: 129 species between 2004 and 2021 in the county Open Spaces. 203 species are on the record for Boulder County (Butterflies and Moths of America 2021) website. The average number of species per year observed within the Open Spaces by this team is 88.