1
|
Kirk DA, Martínez-Lanfranco JA, Forsyth DJ, Martin AE. Farm management and landscape context shape plant diversity at wetland edges in the Prairie Pothole Region of Canada. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2024; 34:e2943. [PMID: 38504599 DOI: 10.1002/eap.2943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 10/29/2023] [Indexed: 03/21/2024]
Abstract
Evaluating the impacts of farming systems on biodiversity is increasingly important given the need to stem biodiversity loss, decrease fossil fuel dependency, and maintain ecosystem services benefiting farmers. We recorded woody and herbaceous plant species diversity, composition, and abundance in 43 wetland-adjacent prairie remnants beside crop fields managed using conventional, minimum tillage, organic, or perennial cover (wildlife-friendly) land management in the Prairie Pothole Region. We used a hierarchical framework to estimate diversity at regional and local scales (gamma, alpha), and how these are related through species turnover (beta diversity). We tested the expectation that gamma richness/evenness and beta diversity of all plants would be higher in remnants adjacent to perennial cover and organic fields than in conventional and minimum tillage fields. We expected the same findings for plants providing ecosystem services (bee-pollinated species) and disservices (introduced species). We predicted similar relative effects of land management on alpha diversity, but with the expectation that the benefits of organic farming would decrease with increasing grassland in surrounding landscapes. Gamma richness and evenness of all plants were highest for perennial cover, followed by minimum tillage, organic, and conventional sites. Bee-pollinated species followed a similar pattern for richness, but for evenness organic farming came second, after perennial cover sites, followed by minimum tillage and conventional. For introduced species, organic sites had the highest gamma richness and evenness. Grassland amount moderated the effect of land management type on all plants and bee-pollinated plant richness, but not as expected. The richness of organic sites increased with the amount of grassland in the surrounding landscape. Conversely, for conventional sites, richness increased as the amount of grassland in the landscape declined. Our results are consistent with the expectation that adopting wildlife-friendly land management practices can benefit biodiversity at regional and local scales, in particular the use of perennial cover to benefit plant diversity at regional scales. At more local extents, organic farming increased plant richness, but only when sufficient grassland was available in the surrounding landscape; organic farms also had the highest beta diversity for all plants and bee-pollinated plants. Maintaining native cover in agroecosystems, in addition to low-intensity farming practices, could sustain plant biodiversity and facilitate important ecosystem services.
Collapse
Affiliation(s)
| | - Juan Andrés Martínez-Lanfranco
- Department of Biological Sciences, University of Alberta, Centennial Center for Interdisciplinary Science Bldg, Edmonton, Alberta, Canada
| | - Douglas J Forsyth
- Canadian Wildlife Service, Environment and Climate Change Canada, Saskatoon, Saskatchewan, Canada
| | - Amanda E Martin
- National Wildlife Research Centre, Environment and Climate Change Canada, Ottawa, Ontario, Canada
- Department of Biology, Carleton University, Ottawa, Ontario, Canada
| |
Collapse
|
2
|
Williams NM, Buderi A, Rowe L, Ward K. Wildflower plantings enhance nesting opportunities for soil-nesting bees. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2024; 34:e2935. [PMID: 38071699 DOI: 10.1002/eap.2935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 09/15/2023] [Indexed: 01/27/2024]
Abstract
Ongoing declines of bees and other pollinators are driven in part by the loss of critical floral resources and nesting substrates. Most conservation/restoration efforts for bees aim to enhance floral abundance and continuity but often assume the same actions will bolster nesting opportunities. Recent research suggests that habitat plantings may not always provide both forage and nesting resources. We evaluated wildflower plantings designed to augment floral resources to determine their ability to enhance nesting by soil-nesting bees over 3 study years in Northern California agricultural landscapes. We established wildflower plantings along borders of annual row crops and paired each with an unplanted control border. We used soil emergence traps to assess nest densities and species richness of soil-nesting bees from spring through late summer at paired field borders planted with wildflowers or maintained conventionally as bare or sparsely vegetated areas, as is typical for the region. We also quantified soil-surface characteristics and flower resources among borders. Wildflower plantings significantly increased nest densities and the richness of bee species using them. Such benefits occurred within the first year of planting and persisted up to 4 years post establishment. The composition of nesting bee communities also differed between wildflower and unenhanced borders. Wildflower plantings differed from controls in multiple characteristics of the soil surface, including vegetation cover, surface microtopography and hardness. Surprisingly, only vegetation cover significantly affected nest densities and species richness. Wildflower plantings are a widespread habitat action with the potential to support wild bees. The demonstrated benefit wildflower plantings had for increasing the nesting of soil-nesting bees greatly augments their relevance for the conservation of wild bee communities in agricultural and other landscapes. Identifying soil-surface characteristics that are important for nesting provides critical information to guide the implementation and management of habitats for bees.
Collapse
Affiliation(s)
- Neal M Williams
- Department of Entomology and Nematology, University of California, Davis, Davis, California, USA
- Graduate Group in Ecology, University of California, Davis, Davis, California, USA
| | - Andrew Buderi
- Department of Entomology and Nematology, University of California, Davis, Davis, California, USA
| | - Logan Rowe
- Department of Entomology and Nematology, University of California, Davis, Davis, California, USA
| | - Kimiora Ward
- Department of Entomology and Nematology, University of California, Davis, Davis, California, USA
| |
Collapse
|
3
|
Wentao M, Shiming T, Le Q, Weibo R, Fry EL, De Long JR, Margerison RCP, Yuan C, Xiaomin L. Grazing reduces plant sexual reproduction but increases asexual reproduction: A global meta-analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 879:162850. [PMID: 36931513 DOI: 10.1016/j.scitotenv.2023.162850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 03/09/2023] [Accepted: 03/10/2023] [Indexed: 05/17/2023]
Abstract
Grazing affects grasslands worldwide. However, the global patterns and general mechanisms of how grazing affects plant reproductive traits are poorly understood, especially in the context of different climates and grazing duration. We conducted a meta-analysis of 114 independent grazing studies worldwide that measured plant reproductive traits in grasslands. The results showed that the number of tillers of plant increased under grazing. Grazing did not affect the number of reproductive branches of forbs, but significantly reduced the number of reproductive branches of grasses. Grazing increased the number of vegetative branches of all plants and reduced the proportion of reproductive branches. Grazing significantly reduced the number of flowers in forbs. Seed yield in the two plant functional groups was reduced compared with no-grazing. Under grazing, the sexual reproduction of grasses decreased much more substantially than that of forbs. This may be due to biomass allocation pattern of grasses under grazing (i.e., belowground versus aboveground). Under grazing, plants tended to adopt rapid, low-input asexual reproduction rather than long-term, high-risk sexual reproduction. This study represents the first large-scale evaluation of plant reproductive trait responses under grazing and demonstrates that grazing inhibits sexual reproduction and promotes asexual reproduction. The effect of grazing on plant sexual reproduction was influenced by grazing intensity, mean annual precipitation, and grazing duration. These results will assist in the development of sustainable grazing management strategies to improve the balance between human welfare and grassland ecosystem health.
Collapse
Affiliation(s)
- Mi Wentao
- Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau & Inner Mongolia Key Laboratory of Grassland Ecology, School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China
| | - Tang Shiming
- Key Laboratory of Model Innovation in Forage Production Efficiency, Ministry of Agriculture and Rural Affairs, Institute of Grassland Research, Chinese Academy of Agricultural Sciences, Hohhot 010010, China
| | - Qi Le
- Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau & Inner Mongolia Key Laboratory of Grassland Ecology, School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China
| | - Ren Weibo
- Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau & Inner Mongolia Key Laboratory of Grassland Ecology, School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China; Key Laboratory of Forage Breeding and Seed Production of Inner Mongolia, Inner Mongolia M-Grass Ecology and Environment (Group)Co., Ltd., Hohhot 010016, China.
| | - Ellen L Fry
- Department of Biology, Edge Hill University, Ormskirk, Lancashire L39 4QP, UK
| | - Jonathan R De Long
- Department of Ecosystem and Landscape Dynamics, Institute of Biodiversity and Ecosystem Dynamics (IBED-ELD), University of Amsterdam, P.O. Box 94240, 1090 GE Amsterdam, the Netherlands
| | - Reuben C P Margerison
- Department of Earth and Environmental Sciences, The University of Manchester, Manchester M13 9PL, UK
| | - Chi Yuan
- Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau & Inner Mongolia Key Laboratory of Grassland Ecology, School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China
| | - Liu Xiaomin
- Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau & Inner Mongolia Key Laboratory of Grassland Ecology, School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China
| |
Collapse
|
4
|
Gardein H, Fabian Y, Westphal C, Tscharntke T, Hass A. Ground-nesting bees prefer bare ground areas on calcareous grasslands. Glob Ecol Conserv 2022. [DOI: 10.1016/j.gecco.2022.e02289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
|
5
|
Duquette CA, Hovick TJ, Geaumont BA, Harmon JP, Limb RF, Sedivec KK. Spatially discrete disturbance processes enhance grassland floral resources. J Appl Ecol 2022. [DOI: 10.1111/1365-2664.14178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Cameron A. Duquette
- New Mexico State University Plant and Environmental Science Las Cruces NM USA
| | | | | | | | - Ryan F. Limb
- North Dakota State University, Range Science Fargo ND USA
| | | |
Collapse
|
6
|
Insect Abundance and Diversity Respond Favorably to Vegetation Communities on Interim Reclamation Sites in a Semi-Arid Natural Gas Field. LAND 2022. [DOI: 10.3390/land11040527] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Natural resource extraction has been linked to habitat loss and declines in biodiversity. Insects, the most diverse and abundant animals on Earth, provide a wide array of critical ecosystem services, but are typically understudied in terrestrial restoration projects. Here, we examine how insects and other arthropods respond to reclamation efforts in the Pinedale Anticline natural gas field in semi-arid Wyoming, USA. Vegetation on two-year-old well pads seeded with native grass or one-year-old well pads seeded with a native annual forb, Rocky Mountain bee plant (Cleomeserrulata), was measured and compared to reference areas adjacent to the well pads with a free software program called SamplePoint. Reference areas in the Pinedale Anticline natural gas field consist primarily of decadent sagebrush stands with low floral diversity. Insect and arthropod communities were also collected and assessed for family richness and abundance on these well pads and reference areas over two years. Based on the mass flowering hypothesis, we expected higher insect abundance and diversity on well pads seeded with the Rocky Mountain bee plant compared to adjacent reference areas. Based on the plant vigor hypothesis, we expected higher insect abundance and diversity on well pads seeded with native grass than reference communities. In year one, 893 insects from 30 insect families with an additional 12 arthropods from 4 families were captured. In year two, 685 insects from 17 families were collected. Reclaimed well pads had significantly higher abundance in both years and vegetation types. In year one, we did not detect a significant difference in richness on native-grass-treated well pads vs. the reference site. We found a significant difference in richness on bee-plant-treated well pads vs. the reference in both years, as well as native-grass-treated well pads vs. the reference in year two. Implications of these findings are discussed in the manuscript.
Collapse
|
7
|
Orr MC, Jakob M, Harmon-Threatt A, Mupepele AC. A review of global trends in the study types used to investigate bee nesting biology. Basic Appl Ecol 2022. [DOI: 10.1016/j.baae.2022.03.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
8
|
Noss RF, Cartwright JM, Estes D, Witsell T, Elliott G, Adams D, Albrecht M, Boyles R, Comer P, Doffitt C, Faber‐Langendoen D, Hill J, Hunter WC, Knapp WM, Marshall ME, Singhurst J, Tracey C, Walck J, Weakley A. Improving species status assessments under the U.S. Endangered Species Act and implications for multispecies conservation challenges worldwide. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2021; 35:1715-1724. [PMID: 34057264 PMCID: PMC9292301 DOI: 10.1111/cobi.13777] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 05/06/2021] [Accepted: 05/17/2021] [Indexed: 06/12/2023]
Abstract
Despite its successes, the U.S. Endangered Species Act (ESA) has proven challenging to implement due to funding limitations, workload backlog, and other problems. As threats to species survival intensify and as more species come under threat, the need for the ESA and similar conservation laws and policies in other countries to function efficiently has grown. Attempts by the U.S. Fish and Wildlife Service (USFWS) to streamline ESA decisions include multispecies recovery plans and habitat conservation plans. We address species status assessment (SSA), a USFWS process to inform ESA decisions from listing to recovery, within the context of multispecies and ecosystem planning. Although existing SSAs have a single-species focus, ecosystem-based research can efficiently inform multiple SSAs within a region and provide a foundation for transition to multispecies SSAs in the future. We considered at-risk grassland species and ecosystems within the southeastern United States, where a disproportionate number of rare and endemic species are associated with grasslands. To initiate our ecosystem-based approach, we used a combined literature-based and structured World Café workshop format to identify science needs for SSAs. Discussions concentrated on 5 categories of threats to grassland species and ecosystems, consistent with recommendations to make shared threats a focus of planning under the ESA: (1) habitat loss, fragmentation, and disruption of functional connectivity; (2) climate change; (3) altered disturbance regimes; (4) invasive species; and (5) localized impacts. For each threat, workshop participants identified science and information needs, including database availability, research priorities, and modeling and mapping needs. Grouping species by habitat and shared threats can make the SSA process and other planning processes for conservation of at-risk species worldwide more efficient and useful. We found a combination of literature review and structured discussion effective for identifying the scientific information and analysis needed to support the development of multiple SSAs. Article impact statement: Species status assessments can be improved by an ecosystem-based approach that groups imperiled species by shared habitats and threats.
Collapse
Affiliation(s)
- Reed F. Noss
- Florida Institute for Conservation Science and Southeastern Grasslands InitiativeMelroseFloridaUSA
| | | | - Dwayne Estes
- Southeastern Grasslands InitiativeAustin Peay State UniversityClarksvilleTennesseeUSA
| | - Theo Witsell
- Southeastern Grasslands InitiativeAustin Peay State UniversityClarksvilleTennesseeUSA
| | - Gregg Elliott
- Southeastern Grasslands InitiativeAustin Peay State University, K Gregg ConsultingClarksvilleTennesseeUSA
| | - Daniel Adams
- U.S. Fish and Wildlife ServiceCookevilleTennesseeUSA
| | - Matthew Albrecht
- Center for Conservation and Sustainable DevelopmentMissouri Botanical GardenSt. LouisMissouriUSA
| | - Ryan Boyles
- U.S. Geological SurveySoutheast Climate Adaptation Science CenterRaleighNorth CarolinaUSA
| | | | - Chris Doffitt
- Natural Areas RegistryLouisiana Department of Wildlife & FisheriesPinevilleLouisianaUSA
| | | | - JoVonn Hill
- Mississippi Entomological MuseumMississippi State UniversityStarkvilleMississippiUSA
| | - William C. Hunter
- U.S. Fish and Wildlife ServiceNational Wildlife Refuge SystemAtlantaGeorgiaUSA
| | - Wesley M. Knapp
- North Carolina Natural Heritage ProgramAshevilleNorth CarolinaUSA
| | | | - Jason Singhurst
- Texas Parks and Wildlife DepartmentNongame and Rare Species ProgramAustinTexasUSA
| | | | - Jeffrey Walck
- Department of BiologyMiddle Tennessee State UniversityMurfreesboroTennesseeUSA
| | - Alan Weakley
- North Carolina Botanical GardenUniversity of North Carolina, and Southeastern Grasslands InitiativeChapel HillNorth CarolinaUSA
| |
Collapse
|
9
|
Cutter J, Geaumont B, McGranahan D, Harmon J, Limb R, Schauer C, Hovick T. Cattle and sheep differentially alter floral resources and the native bee communities in working landscapes. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2021; 31:e02406. [PMID: 34245625 DOI: 10.1002/eap.2406] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 02/09/2021] [Accepted: 03/03/2021] [Indexed: 06/13/2023]
Abstract
Within agricultural landscapes, native bees often rely on limited natural and seminatural lands to provide the majority of the food and nesting resources that sustain them. To understand better how management can affect pollinators in these seminatural areas, we compared how sheep or cattle herbivory influenced floral resources and bee communities in low-diversity, former Conservation Reserve Program (CRP) pastures managed with patch-burn grazing. We sampled bee communities and floral resources three times per season in 2017, 2018, and 2019. We used plant-pollinator line transect sampling and collected bees and counted all flowering stems within 1 m. Across all years, we found that floral abundance, floral richness, floral diversity (Simpson's) and bee richness and abundance were significantly higher in cattle pastures compared to sheep. In cattle pastures, 46 native bee species plus honey bees interacted with 25 of 68 available flowering forbs. In sheep pastures, we recorded 14 native bee species and honey bees interacted with 10 of 34 flowering species. Native bee abundance and native bee richness were best explained by models that included an interaction of floral richness and year. Overall, our results suggest that season-long sheep grazing in low-diversity grasslands greatly reduces available floral resources and correlates with much lower bee abundance and native bee diversity. Given the importance of pollinators to natural and agricultural systems, it is imperative that we take proactive actions to increase forb richness and native flower abundance in seminatural lands to maintain a more diverse and resilient bee community that can continue to support pollination services and global food security.
Collapse
Affiliation(s)
- Jasmine Cutter
- School of Natural Resource Sciences-Range Science Program, North Dakota State University, Fargo, North Dakota, 58108, USA
- Hettinger Research Extension Center, North Dakota State University, Hettinger, North Dakota, 58639, USA
| | - Benjamin Geaumont
- Hettinger Research Extension Center, North Dakota State University, Hettinger, North Dakota, 58639, USA
| | - Devan McGranahan
- School of Natural Resource Sciences-Range Science Program, North Dakota State University, Fargo, North Dakota, 58108, USA
| | - Jason Harmon
- School of Natural Resource Sciences-Entomology Department, North Dakota State University, Fargo, North Dakota, 58108, USA
| | - Ryan Limb
- School of Natural Resource Sciences-Range Science Program, North Dakota State University, Fargo, North Dakota, 58108, USA
| | - Chris Schauer
- Hettinger Research Extension Center, North Dakota State University, Hettinger, North Dakota, 58639, USA
| | - Torre Hovick
- School of Natural Resource Sciences-Range Science Program, North Dakota State University, Fargo, North Dakota, 58108, USA
| |
Collapse
|
10
|
Bruninga‐Socolar B, Griffin SR, Portman ZM, Gibbs J. Variation in prescribed fire and bison grazing supports multiple bee nesting groups in tallgrass prairie. Restor Ecol 2021. [DOI: 10.1111/rec.13507] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
| | - Sean R. Griffin
- Department of Integrative Biology Michigan State University East Lansing MI U.S.A
- W.K. Kellogg Biological Station Michigan State University Hickory Corners MI U.S.A
| | | | - Jason Gibbs
- Department of Entomology University of Manitoba Winnipeg MB Canada
| |
Collapse
|
11
|
Goldas CDS, Podgaiski LR, Silva CVC, Mendonça MDS. Burning for grassland pollination: Recently burned patches promote plant flowering and insect pollinators. AUSTRAL ECOL 2021. [DOI: 10.1111/aec.13108] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Camila da Silva Goldas
- Laboratório de Ecologia de Interações Departamento de Ecologia Universidade Federal do Rio Grande do Sul, UFRGS Avenida Bento Gonçalves 9500 Porto Alegre RS 91540‐000 Brazil
| | - Luciana Regina Podgaiski
- Laboratório de Ecologia de Interações Departamento de Ecologia Universidade Federal do Rio Grande do Sul, UFRGS Avenida Bento Gonçalves 9500 Porto Alegre RS 91540‐000 Brazil
| | - Carolina Veronese Corrêa Silva
- Laboratório de Ecologia de Interações Departamento de Ecologia Universidade Federal do Rio Grande do Sul, UFRGS Avenida Bento Gonçalves 9500 Porto Alegre RS 91540‐000 Brazil
| | - Milton de Souza Mendonça
- Laboratório de Ecologia de Interações Departamento de Ecologia Universidade Federal do Rio Grande do Sul, UFRGS Avenida Bento Gonçalves 9500 Porto Alegre RS 91540‐000 Brazil
| |
Collapse
|
12
|
Griffin SR, Bruninga-Socolar B, Gibbs J. Bee communities in restored prairies are structured by landscape and management, not local floral resources. Basic Appl Ecol 2021. [DOI: 10.1016/j.baae.2020.12.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
13
|
Galbraith SM, Cane JH, Rivers JW. Wildfire severity influences offspring sex ratio in a native solitary bee. Oecologia 2021; 195:65-75. [PMID: 33392790 DOI: 10.1007/s00442-020-04809-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 11/19/2020] [Indexed: 10/22/2022]
Abstract
Although ecological disturbances can have a strong influence on pollinators through changes in habitat, virtually no studies have quantified how characteristics of wildfire influence the demography of essential pollinators. Nevertheless, evaluating this topic is critical for understanding how wildfire is linked to pollinator population dynamics, particularly given recent changes in wildfire frequency and severity in many regions of the world. In this study, we measured the demographic response of the blue orchard bee (Osmia lignaria) across a natural gradient of wildfire severity to assess how variation in wildfire characteristics influenced reproductive output, offspring sex ratio, and offspring mass. We placed nest blocks with a standardized number and sex ratio of pre-emergent adult bees across the wildfire gradient, finding some evidence for a positive but highly variable relationship between reproductive output and fire severity surrounding the nest site at both local (100 m) and landscape (750 m) scales. In addition, the production of female offspring was > 10% greater at nest sites experiencing the greatest landscape-scale fire severity relative to the lowest-severity areas. The finding that blue orchard bees biased offspring production towards the more expensive offspring sex with increasing fire severity shows a functional response to changes in habitat quality through increased density of flowering plants. Our findings indicate that burned mixed-conifer forest provides forage for the blue orchard bee across a severity gradient, and that the increase in floral resources that follows high-severity fire leads females to shift resource allocation to the more costly sex when nesting.
Collapse
Affiliation(s)
- Sara M Galbraith
- Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR, USA.
- Department of Forest Resources, Engineering, and Management, Oregon State University, Corvallis, OR, USA.
| | - James H Cane
- USDA-ARS Pollinating Insects Research Unit, Logan, UT, USA
| | - James W Rivers
- Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR, USA
- Department of Forest Resources, Engineering, and Management, Oregon State University, Corvallis, OR, USA
| |
Collapse
|
14
|
Cariveau DP, Bruninga-Socolar B, Pardee GL. A review of the challenges and opportunities for restoring animal-mediated pollination of native plants. Emerg Top Life Sci 2020; 4:ETLS20190073. [PMID: 32556128 PMCID: PMC7326338 DOI: 10.1042/etls20190073] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 05/26/2020] [Accepted: 05/27/2020] [Indexed: 01/08/2023]
Abstract
Ecological restoration is increasingly implemented to reverse habitat loss and concomitant declines in biological diversity. Typically, restoration success is evaluated by measuring the abundance and/or diversity of a single taxon. However, for a restoration to be successful and persistent, critical ecosystem functions such as animal-mediated pollination must be maintained. In this review, we focus on three aspects of pollination within ecological restorations. First, we address the need to measure pollination directly in restored habitats. Proxies such as pollinator abundance and richness do not always accurately assess pollination function. Pollen supplementation experiments, pollen deposition studies, and pollen transport networks are more robust methods for assessing pollination function within restorations. Second, we highlight how local-scale management and landscape-level factors may influence pollination within restorations. Local-scale management actions such as prescribed fire and removal of non-native species can have large impacts on pollinator communities and ultimately on pollination services. In addition, landscape context including proximity and connectivity to natural habitats may be an important factor for land managers and conservation practitioners to consider to maximize restoration success. Third, as climate change is predicted to be a primary driver of future loss in biodiversity, we discuss the potential effects climate change may have on animal-mediated pollination within restorations. An increased mechanistic understanding of how climate change affects pollination and incorporation of climate change predictions will help practitioners design stable, functioning restorations into the future.
Collapse
Affiliation(s)
- Daniel P Cariveau
- Department of Entomology, University of Minnesota, St. Paul, MN, U.S.A
| | | | | |
Collapse
|
15
|
Stein DS, Debinski DM, Pleasants JM, Toth AL. Evaluating Native Bee Communities and Nutrition in Managed Grasslands. ENVIRONMENTAL ENTOMOLOGY 2020; 49:717-725. [PMID: 32215621 PMCID: PMC7293027 DOI: 10.1093/ee/nvaa009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Indexed: 05/08/2023]
Abstract
Native pollinators are important for providing vital services in agroecosystems; however, their numbers are declining globally. Bees are the most efficient and diverse members of the pollinator community; therefore, it is imperative that management strategies be implemented that positively affect bee community composition and health. Here, we test responses of the bee and flowering plant communities to land management treatments in the context of grasslands in the upper Midwestern United States, a critical area with respect to bee declines. Twelve sites were selected to examine floral resources and wild bee communities based on three different types of grasslands: tallgrass prairie remnants, ungrazed restorations, and grazed restorations. Total bee abundance was significantly higher in ungrazed restorations than remnants, but there were no significant differences among grasslands in community composition or Shannon diversity. Across the three grassland types we also examined mass and lipid stores as nutritional health indicators in three sweat bees (Halictidae), Augochlora pura, Agapostemon virescens, and Halictus ligatus. Although there were no differences in lipid content, total average bee mass was significantly higher in Ag. virescens collected from ungrazed restorations as compared to remnants. Floral abundance of native and non-native species combined was significantly higher in grazed restorations compared to remnants and ungrazed restorations. However, ungrazed restorations had higher abundance and richness of native flowering ramets. These data suggest that bee abundance and nutrition are driven by high abundance of native flowering plant species, rather than total flowering plants.
Collapse
Affiliation(s)
- D S Stein
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA
- Corresponding author, e-mail:
| | - D M Debinski
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA
- Department of Ecology, Montana State University, Bozeman, MT
| | - J M Pleasants
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA
| | - A L Toth
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA
| |
Collapse
|