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1. Adapting to changing methodology in a long‐term experiment

   https://doi.org/10.1002/ecs2.4951  

   McNamara_Manning, Katherine; Perrone, Julia; Petrycki, Stephanie; Landis, Douglas A; Bahlai, Christie A (July 2024, Ecosphere)

   Abstract Long‐term experiments are critical for understanding ecological processes, but their management comes with unique challenges. As time passes, projects may encounter unavoidable changes due to external factors, like availability of materials, affecting aspects of their research methodology. At the Kellogg Biological Station Long‐Term Ecological Research Site, one of the many National Science Foundation‐funded long‐term research stations, a three‐decade project recently experienced a supply‐chain‐induced change in insect sampling methodology in their lady beetle observation study. Since 1989, lady beetles (Coleoptera: Coccinellidae) have been sampled weekly over the growing season using yellow sticky cards. In 2021, the original sticky traps were discontinued by the manufacturer and replaced with a similar, but not identical trap. We conducted a 3‐year study while the new traps were phased in to examine how the trap change would impact the observed biodiversity patterns at the site. We examined community metrics and individual taxa captures to examine within‐year and between‐year differences in performance between the card types. Overall, we noted several small but statistically detectable differences in capture patterns between the two trap types. After accounting for other sources of variation, we observed a difference in Shannon diversity of insects captured on the two card types, but not richness or abundance, for the overall insect community. Yet, these differences were dwarfed by the magnitude of difference observed between years within card types. For individual taxa, similar patterns held: between trap differences could be detected statistically, but the number of differences in capture rate between trap types was less than the number of differences observed for the same trap, between years. Thus, we conclude that while subtle changes in methodology could impact data produced in long‐term experiments; in this case, the magnitude of this change is smaller than other factors such as time and plant treatment. However, if sustained changes in the capture rates of focal taxa are observed, future data users may use our observations to specifically quantify and correct for these shifting patterns related to the protocol change. 

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2. Multicellularity drives ecological diversity in a long-term evolution experiment

   https://doi.org/10.1038/s41559-024-02391-y  

   Ratcliff, William C; Pineau, Rozenn (May 2024, Nature Ecology & Evolution)
3. Getting better with age: Lessons from the Kenya Long‐term Exclosure Experiment

   https://doi.org/10.1111/ele.14466  

   Riginos, C; Kimuyu, DM; Veblen, KE; Porensky, L M; Odadi, WO; Sensenig, RL; Wells, HBM; Young, TP (December 2024, Ecology Letters)

   Abstract The Kenya long‐term exclosure experiment (KLEE) was established in 1995 in semi‐arid savanna rangeland to examine the separate and combined effects of livestock, wildlife and megaherbivores on their shared environment. The long‐term nature of this experiment has allowed us to measure these effects and address questions of stability and resilience in the context of multiple drought‐rainy cycles. Here we outline lessons learned over the last 29 years, and how these inform a fundamental tension in long‐term studies: how to balance the need for question‐driven research with the intangible conviction that long‐term data will yield valuable findings. We highlight the value of (1) identifying experimental effects that take many years to manifest, (2) quantifying the effects of different years (including droughts) and (3) capturing the signatures of anthropogenic change. We also highlight the potential for long‐term studies to create a collaborative community of scientists that brings new questions and motivates continued long‐term study. 

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4. Revisiting the Design of the Long-Term Evolution Experiment with Escherichia coli

   https://doi.org/10.1007/s00239-023-10095-3  

   Lenski, Richard E. (June 2023, Journal of Molecular Evolution)
5. SBC LTER: Reef: Long-term experiment: Kelp removal: Invertebrate and algal density

   https://doi.org/10.6073/pasta/0c6c40d38f5143c7d56f61c455f7fe9b  

   Reed, Daniel C; Miller, Robert J (January 2024, Environmental Data Initiative)

   These data describe the abundance of common reef associated species of macro invertebrates and macroalgae within permanent plots of a long-term experiment designed to examine trajectories of change in the structure and productivity of kelp forest communities in response to changes in the frequency and severity of disturbance to giant kelp. The number of individuals of approximately 50 taxa were recorded by divers along 40 m transects within each plot. Small species of macroalgae and macinvertebrates were counted within six permanent 1 m2 quadrats positioned uniformly along the 40 m transect, while larger species were counted within four contiguous 20 m2 sub-sections of each 40 m x 2 m transect. Also included at the quadrat scale are estimates of an average size-related measurement of each species, which was developed specifically for each species for the purpose of estimating its biomass. The experiment was initiated in 2008 at five reef sites along the mainland coast of the Santa Barbara Channel and included an annual kelp removal treatment designed to simulate increases in the frequency and severity of winter wave disturbance and a continual kelp removal treatment that allowed the effects of giant kelp on the community to be evaluated. The last experimental removals of giant kelp occurred in winter 2016 or winter 2017, depending on the site. Data collection continued in all plots until spring 2023 to document the recovery trajectory of the reef fish community following the cessation of experimental kelp removal. 

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