Mont A. Cazier

Invasive sandburs (Cenchrus spp.), tropical and subtropical plants, are preferred in grasslands and agricultural ecosystems worldwide, causing significant crop production losses and reducing native biodiversity. Integrating phylogenetic relatedness and potentially suitable habitats (PSHs) to identify areas at risk of invasion is critical for prioritizing management efforts and supporting decisions on early warning and surveillance for sandbur invasions. However, despite risk assessments for individual Cenchrus species, the combined analysis of suitable habitats and phylogenetic relationships remains unclear. Therefore, this study aims to assess the invasion risk regions—including PSHs, species richness (SR), and phylogenetic structure—of eight invasive and potentially invasive sandburs in China, to quantify their niche overlap and identify driving factors. Our results showed that the phylogenetic distance of potentially invasive sandburs was closely related to invasive sandburs. Especially, three potentially invasive sandburs, C. ciliaris, C. setigerus, and C. myosuroides, possessed invasion potential resulting from close phylogenetic relatedness and high climatic suitability compared with invasive sandburs. The PSHs for invasive sandburs were distributed in wider regions except northwest China and had higher suitability to different environmental conditions. Potentially invasive sandburs were primarily located in southwestern and southern China driven by precipitation, especially, being inspected in Guangdong, Hainan, and Yunnan on numerous occasions, or potentially introduced in Guangxi, Taiwan, and Fujian for sandburs invasion hotspots. The phylogenetic clustering for eight sandburs occurred in the eastern, center, and southern coastal China, where higher SR in distribution was correlated with invasion hotspots. The SR and phylogenetic relatedness metrics were related to temperature and topographic variables. Totally, the expansion and invasion risk could be increased toward higher latitudes under future global warming. These findings offer novel insights for the prevention and management of sandburs invasions.

The Mojave and Sonoran Deserts, recognized as a global hotspot for bee biodiversity, are experiencing habitat degradation from urbanization, utility‐scale solar energy (USSE) development, and climate change. In this study, we evaluated the current and future distribution of bee diversity, assessed how protected areas safeguard bee species richness, and predicted how global change may affect bees across the region. Using Joint Species Distribution Models (JSDMs) of 148 bee species, we project changes in species distributions, occurrence area, and richness under four global change scenarios between 1971 and 2050. We evaluated the threat posed by USSE development and predicted how climate change will affect the suitability of protected areas for conservation. Our findings indicate that changes in temperature and precipitation do not uniformly affect bee richness. Lower elevation protected areas are projected to experience mean losses of up to 5.8 species, whereas protected areas at higher elevations and transition zones may gain up to 7.8 species. Areas prioritized for future USSE development have an average species richness of 4.2 species higher than the study area average, and lower priority “variance” areas have 8.2 more species. USSE zones are expected to experience declines of up to 8.0 species by 2050 due to climate change alone. Despite the importance of solitary bees for pollination, their diversity is often overlooked in land management decisions. Our results show the utility of JSDMs for leveraging existing collection records to ease the inclusion of data‐limited insect species in land management decision‐making.

Island ecosystems have significant conservation value owing to their higher endemic biotas. Moreover, studies of regional communities that compare differences in species composition (species dissimilarity) among islands and the mainland suggest that community assembly on islands is different from that on the mainland. However, the uniqueness of island biotic assembly has been little studied at the global scale, nor have phylogenetic information or alien species been considered in these patterns. We evaluate taxonomic and phylogenetic change from one community to the next, focusing on differences in species composition between mainland-mainland (M-M) pairs compared to differences between mainland-island pairs (M-I) and between island-island pairs (I-I), using herpetofauna on islands and adjacent mainland areas worldwide. Our analyses detect greater taxonomic and phylogenetic dissimilarity for M-I and I-I comparisons than predicted by M-M model, indicating different island herpetofauna assembly patterns compared with mainland counterparts across the world. However, this higher M-I dissimilarity has been significantly decreased after considering alien species. Our results provide global evidence on the importance of island biodiversity conservation from the aspect of both the taxonomic and phylogenetic uniqueness of island biotic assembly.

Predicting global change effects poses significant challenges due to the intricate interplay between climate change and anthropogenic stressors in shaping ecological communities and their function, such as pest outbreak risk. Termites are ecosystem engineers, yet some pest species are causing worldwide economic losses. While habitat fragmentation seems to drive pest-dominated termite communities, its interaction with climate change effect remains unknown. We test whether climate and habitat fragmentation interactively alter interspecific competition that may limit pest termite risk. Leveraging global termite co-occurrence including 280 pest species, we found that competitively superior termite species (e.g., large bodied) increased in large and continuous habitats solely at high precipitation. While competitive species suppressed pest species globally, habitat fragmentation drove pest termite risk only in humid biomes. Unfortunately, hu- mid tropics have experienced vast forest fragmentation and rainfall reduction over the past decades. These stressors, if not stopped, may drive pest termite risk, potentially via competitive release.

AbstractBees (Hymenoptera: Apoidea) are vital components of global ecosystems, yet knowledge of their distribution is limited in many regions. Washington state is located in an ecologically diverse part of North America and encompasses habitat types and plant communities known for high bee species richness. To establish a baseline for future studies on bee communities in the state, we used published and unpublished datasets to develop a preliminary annotated checklist of bees occurring in Washington state. We document, with high confidence, 565 species of bees in Washington and identify an additional 102 species likely to occur in the state. We anticipate future research survey efforts, such as the newly initiated Washington Bee Atlas, will discover several species that have the potential to occur in Washington and provide new data for 84 species which have not been recorded in more than 50 years.

Pinyon–juniper (PJ) woodlands are among the most widespread ecosystems in rangelands of western North America, supporting diverse wildlife habitat, recreation, grazing, and cultural/spiritual enrichment. Anticipating future distribution shifts under changing climate will be critical to climate adaptation and conservation efforts in these ecosystems. Here, we evaluate drivers of PJ tree species’ distributions and project changes in response to future climate change. We developed species distribution models with dryland-focused predictors to project environmental suitability changes across the entirety of three pinyon and six juniper species ranges. We identify areas of robust suitability change by combining suitability projections from multiple emissions scenarios and time periods. PJ species’ suitabilities respond to many temperature and moisture covariates expected to change in the future. Projected responses among PJ species are highly variable, ranging from modest declines with concurrent gains for overall little net change to wide-ranging declines with no gains for overall range contractions. Environmental suitability is projected to decline broadly across the arid United States Southwest and remain relatively stable across the northern Great Basin and Colorado Plateau. Our results suggest unique responses of PJ species to future climate change. We found that species were projected to experience more losses than gains in suitability, for overall range shrinks rather than shifts. Land managers have the capacity to increase woodland resilience to drought, and our results can inform rangeland-wide management planning and conservation efforts in PJ woodlands.

Nonnative invasive plants (weeds) negatively impact native ecosystems, and their effects are likely to increase with continuing global trade. Biological weed control has been employed as a cost-effective and sustainable management option for weeds in the USA since 1902. Biological control programs require careful prioritization of target weeds to ensure the most appropriate targets are selected to obtain the greatest beneficial outcomes with available resources. The Biological Control Target Selection (BCTS) system was developed by researchers in South Africa as an objective, transparent approach to prioritizing new weed biological control targets. The BCTS system was recently modified and applied to 295 state-regulated weeds in the western USA for which no biological control agents have yet been released. This paper presents the results of that application, identifying the most suitable candidates for new biological control programs as well as problematic weeds for which the likelihood of successful biological control is low.Top-ranked species in the western USA are biennial or perennial weeds that occur in stable habitats, are established in more than one state, have traits deemed difficult to control with conventional methods, have large negative impacts and no conflicts of interest outside of the horticultural industry, and have substantial information available on potential biocontrol agents. Fifteen of the 20 top-ranked species are already targets of ongoing biological control programs in the USA. When species with current programs are excluded from the analysis, the next 20 top-ranked species largely differ by having less information available on potential biological control agents and having native or economically important congeners in the USA. Results from this framework provide valuable insights to the prioritization of current and future biocontrol research programs in the western USA.

As an invasive plant, Solanum elaeagnifolium has posed a serious threat to agriculture and natural ecosystems worldwide. In order to better manage and limit its spread, we established niche models by combining distribution information and climate data from the native and invasive ranges of S. elaeagnifolium to analyze its niche changes during its colonization. Additionally, we evaluated its global invasion risk. Our results showed that the distribution of S. elaeagnifolium is affected by temperature, precipitation, altitude, and human activities. Solanum elaeagnifolium exhibits different degrees of niche conservatism and niche shift in different invasion ranges.During the global invasion of S. elaeagnifolium, both the niche shift and conservatism were observed, however, niche shift was particularly significant due to the presence of unoccupied niches (niche unfilling). Solanum elaeagnifolium generally occupied a relatively stable niche. However, a notable expansion was observed primarily in Europe and China. In Australia and Africa, its niche largely remains a subset of its native niche. Compared to the niche observed in its native range, its realized niche in China and Europe has shifted toward lower temperature and higher precipitation levels. Conversely, in Africa, the niche has shifted toward lower precipitation levels, while in Australia, it has shifted toward higher temperature. Our model predicted that S. elaeagnifolium has high invasion potential in many countries and regions. The populations of S. elaeagnifolium in China and Africa have reached the adapted stage, while the populations in Australia and Europe are currently in the stabilization stage. In addition, our research suggests that the potential distribution of S. elaeagnifolium will expand further in the future as the climate warms. All in all, our study suggests that S. elaeagnifolium has high potential to invade globally. Due to its high invasive potential, global surveillance and preventive measures are necessary to address its spread.

To date, the knowledge of bee diversity in the Baja California Peninsula has primarily relied on large, sporadic expeditions from the first half of the 20th century. To address the knowledge gaps, we conducted extensive fieldwork from 2019 to 2023, visited entomological collections in Mexico and USA, and accessed digital databases and community science platforms to compile records. As a result of our field surveys, we identified 521 morphospecies, with 350 recognized as valid species, including 96 new records for the Baja California Peninsula and 68 new findings for Mexico, including the rediscovery of Megachile seducta Mitchell, 1934, ranked as possibly extinct. Additionally, museum visits added 24 new species records for the peninsula, including 12 new to Mexico. Integrating the new and existing records results in a comprehensive checklist that documents 728 species for the peninsula, 613 for Baja California, and 300 for Baja California Sur. Notably, 62 species are endemic to the peninsula, of which 22 are only found in Baja California, and 23 in Baja California Sur. Our findings show a greater bee diversity in northern latitudes, with a sharp decrease to the central and southern peninsula, which corresponds to the geographic distribution of the records. This supports the premise that the Baja California peninsula remains an unexplored area and highlights the importance of conducting studies like the one presented here.  

From the largest nesting aggregation ever recorded for the genus Melissodes, we took diverse bionomic measurements of Melissodes bimaculatus (Two-spotted Longhorn Bee). Our results show a protandrous reproductive strategy occurring from July through August in New York. We observed parasitism by the kleptoparasitic bee Triepeolus simplex as well as nest-architecture modifications to ease this burden that support the selfish-herd hypothesis. In this population, we also found a proclivity for grass (Poaceae) pollen, a previously undocumented diet preference for Two-spotted Longhorn Bees. We further showed that this bee species has widespread climatically suitable habitat, with expected range expansion under future climate conditions. Altogether, our results offer novel insights into the ecology of theTwo-spotted Longhorn Bee and its gregarious nesting behavior.