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1. Historical resurveys provide support for abiotic limits to Argentine ant invasion in southern California

   https://doi.org/10.1007/s10530-025-03583-8  

   Hathaway, Shane; Menke, Sean B; Holway, David A (May 2025, Biological Invasions)

   Abstract Predicting where introduced species will establish and spread remains a central goal of invasion biology. While climate data are often used to forecast potential occurrence at regional scales, environmental filtering can limit susceptibility to invasion at finer scales. Factors underlying such filtering are important to identify, especially when they influence spread into protected areas set aside for conservation. Useful information about factors limiting invasion can be obtained from historical resurveys. Between 2022 and 2024, we used pitfall traps and visual surveys to resurvey 111 sampling points in two protected areas in coastal San Diego County, California (Torrey Pines State Reserve and the Point Loma Ecological Conservation Area) that were originally surveyed for the non-native Argentine ant between 1995 and 1997. The multi-decade time span between the surveys coupled with the observed distributional limits, which have either contracted (Torrey Pines) or appear static (Point Loma), indicate that the Argentine ant has reached the limits of its ability to invade these sites. At Torrey Pines the soil types with the lowest water retention values were the least invaded in the original survey and were overrepresented among retractions observed in the resurvey. These findings are consistent with experimental work demonstrating the central role of soil moisture in limiting Argentine ant spread in seasonally dry areas. Variation in precipitation combined with changes in human water use will likely continue to influence the distribution of the Argentine ant in semiarid regions. These results generally illustrate the value of historical resurveys in clarifying limits to invasion. 

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2. Exploitation of a marine subsidy by a terrestrial invader

   https://doi.org/10.1007/s10530-024-03500-5  

   Winters, Christopher; Jurgela, Grace; Holway, David (January 2025, Biological Invasions)

   Abstract Intertidal environments receive energy from marine ecosystems in the form of marine wrack, which makes up the base of a food web that includes both intertidal and terrestrial consumers. Consumption of wrack by terrestrial consumers can elevate their abundance and alter how they interact with organisms in adjacent terrestrial environments. Although rarely documented, terrestrial invaders may exploit marine wrack subsides and potentially disrupt intertidal and terrestrial food webs. Here, we examine consumption of marine wrack resources by the introduced Argentine ant (Linepithema humile), which occurs commonly on beaches in southern California. In controlled trials the Argentine ant readily scavenged arthropod detritivores (amphipods and flies) abundant in wrack. In spite of obvious risks (e.g., exposure to tides, desiccation, thermal stress) associated with intertidal foraging, Argentine ant activity on beaches was comparable to that in spatially-paired, scrub environments. Foraging on beaches allowed ants to access higher densities of arthropod prey and carrion compared to those found in scrub environments. Stable isotope analyses provide evidence for extensive assimilation of marine-derived resources. Values of δ¹⁵N and δ¹³C for the Argentine ant were higher at beach sites than at scrub sites, and Argentine ant δ¹⁵N values broadly overlapped those of intertidal consumers at beach sites. Although ants are known to forage in intertidal environments, this study provides a novel example of an introduced ant species exploiting a cross-boundary subsidy. 

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3. Direct evidence of native ant displacement by the Argentine ant in island ecosystems

   https://doi.org/10.1007/s10530-019-02121-7  

   Naughton, I. (November 2020, Biological invasions)

   null (Ed.)

   Ecological impacts associated with ant introductions have received considerable attention, but most studies that report on these impacts contrast species assemblages between invaded and uninvaded sites. Given the low inferential power of this type of space-for-time comparison, alternative approaches are needed to evaluate claims that ant invasions drive native species loss. Here, we use long-term data sets from two different Argentine ant eradication programs on the California Channel Islands to examine how the richness and composition of native ant assemblages change before and after invasion (but prior to the initiation of treatments). At four different sites on two different islands, pre-invasion native ant assemblages closely resembled those at uninvaded (control) sites in terms of species richness, species composition, and the presence of multiple indicator species. Invader arrival coincided with large (> 75%) and rapid (within 1 year) declines in species richness, shifts in species composition, and the loss of indicator species. These impacts will hopefully be reversed by the recolonization of formerly invaded areas by native ant species following Argentine ant treatment, and long-term studies of native ant recovery at these sites are ongoing. Unchecked spread of the Argentine ant on other islands in this archipelago, however, poses a grave threat to native ants, which include a number of endemic taxa. 

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4. A third species of the rare millipede genus Apterourus Loomis, 1966 (Diplopoda: Chordeumatida: Striarioidea: Apterouridae)

   https://doi.org/10.64338/im.1159.jphq7  

   Shear, William A; Richart, Casey H; Marek, Paul E (November 2025, Insecta Mundi)

   The millipede genus Apterourus Loomis, 1966, the only genus of the family Apterouridae Loomis, 1966 (Diplopoda: Chordeumatida: Striarioidea), contains two species and is rarely collected. We add a third species from Mt. Palomar, San Diego County, California, USA, Apterourus palomar Shear, Richart and Marek, new species. 

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5. 2025 PG&E Energy Analytics Challenge: Electric Load Forecasting Datasets

   https://doi.org/10.5281/zenodo.17085273  

   Yildirim, Murat; Mansouri, Mahan; Aziz_Ezzat, Ahmed; Yildirim, Murat; Mansouri, Mahan; Aziz_Ezzat, Ahmed (January 2025, Zenodo)

   Summary:   This repository contains the datasets used in the 2025 PG&E Energy Analytics Challenge on Electricity Load Forecasting, co-organized by the IISE Energy Systems Division and the INFORMS Quality, Statistics, and Reliability Section, and graciously sponsored by the Pacific Gas & Electric Company (PG&E).  The repository contains two files: Train.xlsx: Contains three years of hourly electric loads from San Diego, California (Years 2020-2022), as well as exogenous weather information at five neighboring sites within the San Diego area.    Test.xlsx: Contains one year of hourly electric loads from San Diego, California (Year 2023), as as well as exogenous weather information at five neighboring sites within the San Diego area.    Background:  This competition aimed to predict electricity loads for a specific location within the CAISO system. Accurate load forecasting is critical for managing electricity distribution within California’s diverse and dynamic energy market. Load patterns can vary significantly due to factors such as weather conditions, local supply and demand, and the mix of nearby energy generation sources.   During the competition, the specific location and the actual years were not disclosed to the participants. Participants were then asked to generate a year’s worth of load forecasts using historical load values and exogeneous weather information. Predictor data were not allowed to be taken from future time periods: When predicting the load values at a particular day, the model was allowed to only use predictor variable information from that time period or before. For example, if a team is predicting the load for Day 5 Hour 3 in Year 3, the model can only take in predictor values from Day 5 Hour 3 in Year 3, or before. Furthermore, during the competition, the load information for the test set (highlighted in yellow in the test data file) was reserved from all participants, who were asked to submit their predictions for the full year.    This is the second offering of the PG&E Energy Analytics challenge, complementing the first offering in 2024 which focused on electricity price forecasting [Results of the 2024 challenge: Aziz Ezzat, A., Mansouri, M., Yildirim, M., & Fang, X. (2025). IISE PG&E Energy Analytics Challenge 2024: Forecasting day-ahead electricity prices. IISE Transactions, 1–13. https://doi.org/10.1080/24725854.2024.2447049].  

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