Fig 3 - uploaded by Ronald J. Kendall
Content may be subject to copyright.
Milkweed condition by location and date. Stacked bar graphs representing the condition (B Budding, D Dehiscent, F Flowering, SP with Seedpod, SN Senescing, V Vegetative) of milkweed throughout the survey period by location

Milkweed condition by location and date. Stacked bar graphs representing the condition (B Budding, D Dehiscent, F Flowering, SP with Seedpod, SN Senescing, V Vegetative) of milkweed throughout the survey period by location

Source publication
Article
Full-text available
Background: The monarch butterfly (Danaus plexippus) is a conspicuous insect that has experienced a drastic population decline over the past two decades. While there are several factors contributing to dwindling monarch populations, habitat loss is considered the most significant threat to monarchs. In the United States, loss of milkweed, particul...

Context in source publication

Context 1
... Fig. 1. Monarch eggs and larva were also more abundant in Fisher County overall. In contrast, queen eggs and larva were most abundant at Stonewall 2 but appeared to be more evenly distributed throughout the Fisher County sites (Fig. 2). As the sampling period progressed, there were fewer plants sampled with a higher proportion of senescing plants (Fig. ...

Similar publications

Article
Full-text available
The present communication is the first report of new distributional record of Ficus altissima Blume (Moraceae) in Tripura. F. altissima was found to be an important feeding and nesting habitat for forest frugivores, since the genus is very rich in diversity and is considered as a keystone species. This also possesses huge scope to understand the me...

Citations

... These four species were the primary late season monarch larval hosts reported in Central Texas by Calvert (1999). Lynch and Martin (1993) Brym et al. (2020;also unpublished data, D. Berman and K. Baum). ...
Article
Full-text available
South Central US milkweeds (Asclepias) are critical adult nectar and larval food resources for producing the first spring and last summer/fall generations of declining eastern migratory monarch butterflies (Danaus plexippus). This study addresses multiple gaps in assessment of monarch conservation priorities for the South Central US through analyses of monarch larval host selectivity, phenology, and spatial density, as well as the phenology, niche modeled distribution, and land cover selectivity of important milkweed hosts. Results are synthesized to estimate seasonal milkweed resource areas. About 70% of monarch larval activity occurred from mid-March to mid-July (early season) and 30% from mid-August to late November (late season). Twenty-six wild milkweed (Apocynaceae) hosts were mapped, including four new records for North America. Important hosts included Asclepias a. ssp. capricornu, A. viridis, and A. oenotheroides, that were utilized more frequently during early season, and Asclepias latifolia, utilized more frequently during late season. Landscape host selectivity was positive for A. viridis and A. a. ssp. capricornu in late and early seasons, respectively, and negative for A. oenotheroides in late season. Milkweed land cover selectivity was positive for Developed-Open Space and Grassland Herbaceous, and negative for Cultivated Crops and Shrub/Scrub. Seasonal milkweed resource areas and larval spatial densities resolved interior and coastal corridors providing functional connectivity for monarch spring and fall migrations. A potential gap in milkweed resource areas was identified in South Texas. The novel merging of milkweed niche models with larval phenology, host selectivity, milkweed phenology, and land cover selectivity informs conservation assessment.
... As such, research into the restoration and enhancement of monarch habitat in areas outside of the Midwest may yield improved, regionally adapted techniques that could present additional opportunities for monarch conservation. West Texas is one such area where milkweed restoration could be implemented to aid conservation efforts, as high densities of monarch eggs have been documented in this region (Brym et al., 2020). Additionally, while West Texas is sparsely populated and has relatively few monarch conservation initiatives when compared to the central and eastern portions of the state, the large amounts of marginal land in West Texas provide an excellent opportunity for the restoration of monarch habitat. ...
... Nevertheless, the low establishment we observed in A. asperula (<5%) compared to A. latifolia (27-30%) and A. oetheroides (23-33%) is noteworthy (Table 2), particularly considering A. asperula is among the most widely propagated and commonly available milkweed species in our ecoregion (Monarch Watch, 2020). As such, propagating and incorporating more A. latifolia and A. oetheroides into restoration initiatives in West Texas and similar areas may increase the effectiveness of these efforts, especially considering monarch utilization of both species has been documented (Brym et al., 2020). ...
... For instance, Malcolm et al. (1987), Cockrell et al. (1993) and Malcolm et al. (1993) have shown that southern milkweeds are important to spring migration of monarchs, but suspected that these milkweed may become less significant as monarchs move north and plants senesce during the hot and dry summer. In contrast, Zalucki and Rochester (2004) predicted a resurgence in milkweed and monarch activity during cooler and wetter conditions and this was confirmed by reports of monarch breeding in West Texas during a pre-migration in the fall of 2018 (Brym et al., 2020). Indeed, it is likely that both of these scenarios occur, as A. asperula is typically more robust in the spring, whereas A. latifolia and A. oetheroides may thrive later into the year, (Singhurst et al., 2015). ...
Article
The monarch butterfly (Danaus plexippus) is among the best-known insects in the world, renowned for its conspicuousness, spectacular migration, and interesting biology. Unfortunately, monarch populations have declined dramatically due, in large part, to the widespread losses of the milkweed plants which they depend upon for reproduction. This has led to concerted efforts to restore milkweed, particularly in the Midwestern US where most monarch breeding occurs. However, recently there has been a call to expand milkweed restoration across more of the monarch’s migratory distribution, with Southern states, like Texas, being emphasized. In this study, we evaluated the feasibility of milkweed restoration in the Rolling Plains ecoregion of West Texas, an area with numerous reports of monarchs but relatively limited conservation initiatives. We founded milkweed colonies that included four species of milkweed in three counties across West Texas, and the establishment and growth of milkweed in these was monitored for up to four years. Generalized additive mixed-effect models were then used to assess milkweed establishment and growth as a factor of plant age, species, and location. Temporal patterns in establishment and growth were also examined. Milkweed were successfully established across all colonies and as many as 45% of some species persisted four years after being planted. Additionally, we found age (p < 0.001), species (p = 0.02), and location (p = 0.04) to be significant predictors of establishment, while species was a significant predictor of growth (p = 0.001). While more research is needed to assess the restoration of milkweed in West Texas, this is, to our knowledge, the first study to monitor milkweed over an entire season in this area and may provide valuable data to facilitate development of a regionally adapted milkweed restoration strategy.
Preprint
Full-text available
1. Species identification errors may have severe implications for the inference of species distributions. Accounting for misclassification in species distributions is an important topic of biodiversity research. With an increasing amount of biodiversity that comes from Citizen Science projects, where identification is not verified by preserved specimens, this issue is becoming more important. This has often been dealt with by accounting for false positives in species distribution models. However, the problem should account for misclassifications in general. 2. Here we present a flexible framework that accounts for misclassification in the distribution models and provides estimates of uncertainty around these estimates. The model was applied to data on viceroy, queen and monarch butterflies in the United States. The data were obtained from the iNaturalist database in the period 2019 to 2020. 3. Simulations and analysis of butterfly data showed that the proposed model was able to correct the reported abundance distribution for misclassification and also predict the true state for misclassified state.
Preprint
Full-text available
South Central US milkweeds ( Asclepias ) are critical adult nectar and larval food resources for producing the first spring and last summer/fall generations of declining eastern migratory monarch butterflies ( Danaus plexippus ). This study addresses multiple gaps in assessment of monarch conservation priorities for the South Central US through analyses of monarch larval host selectivity, phenology, and spatial density, as well as the phenology, niche modeled distribution, and land cover selectivity of important milkweed hosts. Results are synthesized to estimate seasonal milkweed resource areas. About 70% of monarch larval activity occurred from mid-March to mid-July (early season) and 30% from mid-August to late November (late season). Twenty-six wild milkweed (Apocynaceae) hosts were mapped, including four new records for North America. Important hosts included Asclepias a. ssp. capricornu , A. viridis , and A. oenotheroides , that were utilized more frequently during early season, and Asclepias latifolia , utilized more frequently during late season. Landscape host selectivity was positive for A. viridis and A. a. ssp. capricornu in late and early seasons, respectively, and negative for A. oenotheroides in late season. Milkweed land cover selectivity was positive for Developed-Open Space and Grassland Herbaceous, and negative for Cultivated Crops and Shrub/Scrub. Seasonal milkweed resource areas and larval spatial densities resolved interior and coastal corridors providing functional connectivity for monarch spring and fall migrations. A potential gap in milkweed land cover benefit was identified in South Texas. The novel merging of milkweed niche models with larval phenology, host selectivity, milkweed phenology, and land cover selectivity informs conservation assessment.
Preprint
Full-text available
South-Central US milkweeds ( Asclepias spp.) are critical adult nectar and larval food resources for producing the first spring and last summer/fall generations of declining eastern migratory monarch butterflies ( Danaus plexippus ). MaxEnt niche models were developed for North American ranges of four important South-Central US milkweeds: Asclepias asperula ssp. capricornu , A. viridis , A. oenotheroides , and A. latifolia . Twelve models per species utilized subsets of six to eight of 95 edapho-topo-climatic variables chosen by a random subset feature selection algorithm. Milkweed weekly phenology was compared between early and late season periods of monarch activity. Novel land cover preference risk assessments were developed for milkweeds through land cover utilization-availability analyses, incorporating a novel sample bias reduction method for citizen science data before calculation of relativized electivity index ( E* ) land cover preference. Asclepias a. ssp. capricornu and A. viridis occurred more frequently during early season monarch activity, while A. oenotheroides and A. latifolia occurred more frequently during late season monarch activity. Milkweed utilization of roadsides varied from 6–31%. Developed-Open Space and Grassland Herbaceous land classes generally had highest benefit among milkweeds. Cultivated Crops and Shrub/Scrub had high risk. Combined milkweed high E i * kernel density estimation surfaces resolved interior and coastal corridors of milkweed land cover preference providing functional connectivity for the monarch spring and fall migrations. A potentially critical gap in milkweed land cover benefit connectivity was identified in South Texas. Milkweed land cover preference risk assessments can be used to prioritize milkweed habitat conservation for enhancing monarch migration connectivity across the South-Central US.