Abstract Urbanization has dramatically altered Earth's landscapes and changed a multitude of environmental factors. This has resulted in intense land‐use change, and adverse consequences such as the urban heat island effect (UHI), noise pollution, and artificial light at night (ALAN). However, there is a lack of research on the combined effects of these environmental factors on life‐history traits and fitness, and on how these interactions shape food resources and drive patterns of species persistence. Here, we systematically reviewed the literature and created a comprehensive framework of the mechanistic pathways by which urbanization affects fitness and thus favors certain species. We found that urbanization‐induced changes in urban vegetation, habitat quality, spring temperature, resource availability, acoustic environment, nighttime light, and species behaviors (e.g., laying, foraging, and communicating) influence breeding choices, optimal time windows that reduce phenological mismatch, and breeding success. Insectivorous and omnivorous species that are especially sensitive to temperature often experience advanced laying behaviors and smaller clutch sizes in urban areas. By contrast, some granivorous and omnivorous species experience little difference in clutch size and number of fledglings because urban areas make it easier to access anthropogenic food resources and to avoid predation. Furthermore, the interactive effect of land‐use change and UHI on species could be synergistic in locations where habitat loss and fragmentation are greatest and when extreme‐hot weather events take place in urban areas. However, in some instances, UHI may mitigate the impact of land‐use changes at local scales and provide suitable breeding conditions by shifting the environment to be more favorable for species' thermal limits and by extending the time window in which food resources are available in urban areas. As a result, we determined five broad directions for further research to highlight that urbanization provides a great opportunity to study environmental filtering processes and population dynamics.
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The missing angle: Ecosystem consequences of phenological mismatch
Climate change leads to unequal shifts in the phenology of interacting species, such as consumers and their resources, leading to potential phenological mismatches. While studies have investigated how phenological mismatch affects wild populations, we still lack studies and a framework for investigating how phenological mismatch affects ecosystems, particularly nutrient cycling.
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- Award ID(s):
- 1304523
- NSF-PAR ID:
- 10129799
- Date Published:
- Journal Name:
- Trends in ecology evolution
- Volume:
- 34
- Issue:
- 10
- ISSN:
- 0169-5347
- Page Range / eLocation ID:
- 19-22
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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In coastal western Alaska, we conducted a 3‐year factorial experiment that simulated scenarios of phenological mismatch by manipulating the start of the growing season (3 weeks early and ambient) and grazing times (3 weeks early, typical, 3 weeks late, or no‐grazing) of Pacific black brant (
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Phenological mismatch can occur when plants and herbivores differentially respond to changing phenological cues, such as temperature or snow melt date. This often shifts herbivore feeding to plant stages of lower quality. How herbivores respond to plant quality may be also mediated by temperature, which could lead to temperature-by-phenology interactions. We examined how aphid abundance and mutualism with ants were impacted by temperature and host plant phenology. In this study system, aphids Aphis asclepiadis colonize flowering stalks of the host plant, Ligusticum porteri. Like other aphids, abundance of this species is dependent on ant protection. To understand how host plant phenology and temperature affect aphid abundance, we used a multiyear observational study and a field experiment. We observed 20 host plant populations over five years (2017–2021), tracking temperature and snow melt date as well as host plant phenology and insect abundance. We found host plant and aphid phenology to differentially respond to temperature and snow melt timing. Early snow melt accelerated host plant phenology to a greater extent than aphid phenology, which was more responsive to temperature. Both the likelihood of aphid colony establishment and ant recruitment were reduced when aphids colonized host plants at post-flowering stages. In 2019, we experimentally accelerated host plant phenology by advancing snow melt date by two weeks. We factorially combined this treatment with open top warming chambers surrounding aphid colonies. Greatest growth occurred for colonies under ambient temperatures when they occurred on host plants at the flowering stage. Altogether, our results suggest that phenological mismatch with host plants can decrease aphid abundance, and this effect is exacerbated by temperature increases and changes to the ant–aphid mutualism.more » « less
- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/https://doi.org/10.1016/j.tree.2019.07.019
