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1. Estimating vital rate variation to assess early success of scrub mint translocations

   https://doi.org/10.1111/csp2.12934  

   Koontz, Stephanie M. ; López‐Borghesi, Federico ; Smith, Stacy A. ; Haller Crate, Sarah J. ; Quintana‐Ascencio, Pedro F. ; Menges, Eric S. ( April 2023 , Conservation Science and Practice)

   Species translocations are increasingly common in rare plant conservation. Wild populations can provide basic ecological knowledge to improve their chance of success. In the heavily fragmented Florida scrub, USA, many listed species require translocations to persist, includingDicerandra christmanii. In 1994, we began monitoring the only protected population ofD. christmaniigrowing both in gaps (open areas) within the shrub matrix and on roadsides. In 2010, we augmented this population by adding plants and seeds to unoccupied gaps. In 2012, we introduced plants to a separate protected site to create a new population. We evaluated early translocation success using generalized linear mixed‐effect models of vital rate variation among habitat types. Survival probability increased with size, peaking at 0.6–0.8, and was lowest in augmentations and highest in introductions. Growth increased with plant size across all habitat types, except for the largest adults which experienced senescence. Naturally recruited plants in gaps showed the highest reproduction probability and fecundity at smaller sizes, but larger plants in translocations had the highest fecundity. Yearling recruitment was higher in translocated plants relative to naturally recruited plants in gaps during the initial years following outplanting. Experimental components of translocations also affected outplanting performance with positive effects of fire. These analyses suggest a high potential for translocations to become established and contribute to species recovery.

    

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2. Coping with changing plant–plant interactions in restoration ecology: Effect of species, site, and individual variation

   https://doi.org/10.1111/avsc.12644  

   Garrote, Pedro José ; Castilla, Antonio Ramón ; Fedriani, Jose Maria ( January 2022 , Applied Vegetation Science)

   Alday, Josu (Ed.)

   Abstract Question Nurse–beneficiary plant interactions are often used to restore degraded habitats. However, whether and how shifts in plant–plant interactions along the facilitation–competition continuum alter revegetation success has been seldom considered. To test whether and how shifts in plant–plant interactions (due to woody species identity, study site, early life stage, and individual nurse) might alter plant recruitment and thus the success of revegetation projects, we chose a system comprising the Mediterranean dwarf palm ( Chamaerops humilis ) and seven common woody plant species. Location Two human‐degraded sites within Doñana National Park (southwestern Spain). Methods We carried out several well‐replicated field experiments to compare plant performance (seed survival, seedling emergence, seedling survival, seedling recruitment) in the presence and absence of Chamaerops humilis . Results Chamaerops humilis had marked effects on the performance of woody species that, however, changed among life stages. Depending on woody species identity, seed survival was up to 193 times greater in adjacent open spaces than beneath Chamaerops humilis . Conversely, seedling survival and recruitment were up to 19 times greater beneath Chamaerops humilis than in open spaces. Importantly, none of the studied woody species showed greater accumulated recruitment in open spaces than beneath Chamaerops humilis . Interestingly, we found strong inter‐individual palm variation in the sign and strength of their effect on woody plant performance. Conclusions We found strong seed–seedling conflicts the strength of which was species‐specific. The strong inter‐individual palm variation depicts a facilitation–competition continuum with important implications for restoration. We propose several management recommendations across different hierarchical levels (i.e., from individuals to communities) that may increase plant recruitment and therefore the success of revegetation projects. Our results are particularly relevant for restoring arid, semi‐arid and alpine landscapes worldwide where the nurse–beneficiary plant interactions are critical to ameliorating stressful conditions. 

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3. Opposing deer and caterpillar foraging preferences may prevent reductions in songbird prey biomass in historically overbrowsed forests

   https://doi.org/10.1002/ece3.3497  

   Godfrey, R. Keating ; Yerger, Ellen H. ; Nuttle, Timothy J. ( December 2017 , Ecology and Evolution)

   Overbrowsing by ungulates decimates plant populations and reduces diversity in a variety of ecosystems, but the mechanisms by which changes to plant community composition influence other trophic levels are poorly understood. In addition to removal of avian nesting habitat, browsing is hypothesized to reduce bird density and diversity through reduction of insect prey on browse‐tolerant hosts left behind by deer. In this study, we excluded birds from branches of six tree species to quantify differences in songbird prey removal across trees that vary in deer browse preference. Early in the breeding season, birds preyed on caterpillars at levels proportional to their abundance on each host. Combining these data with tree species composition data from stands exposed to experimentally controlled deer densities over 30 years ago, we tested whether overbrowsing by white‐tailed deer reduces prey biomass long after deer densities are reduced. Our analysis predicts total prey availability in the canopy of regenerating forests is fairly robust to historic exposure to high deer densities, though distribution of prey available from host species changes dramatically. This predicted compensatory effect was unexpected and is driven by high prey abundance on a single host tree species avoided by browsing deer,Prunus serotina. Thus, while we confirm that prey abundance on host trees can act as a reliable predictor for relative prey availability, this study shows that quantifying prey abundance across host trees is essential to understanding how changes in tree species composition interact with ungulate browse preference to determine prey availability for songbirds.

    

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4. Intentions of Landowners towards Active Management of Ecosystem for Deer Habitat

   https://doi.org/10.1007/s00267-023-01810-3  

   Mishra, Bijesh ; Joshi, Omkar ; Chapagain, Binod P. ; Lambert, Lixia He ; Will, Rodney E. ( September 2023 , Environmental Management)

   Active management such as prescribed fire and thinning can restore savanna and prairie ecosystem to maintain a full suite of ecosystem services and create suitable habitat for wildlife species such as white-tailed deer (Odocoileus virginianus). Active management comes with the cost of management and acceptance of management tools. The south-central transitional ecoregion of the USA, which otherwise was a mixture of forest, savanna, and tallgrass prairie, is increasing in woody plant dominance due to the exclusion of fire and other anthropogenic factors. Deer hunting is a vital source of revenue generation to offset the landowner’s management cost in the region. We studied Oklahoma landowners’ perceptions regarding active and sustainable management of forest and rangeland for deer habitat using two established theories of reasoned action and planned behavior as well as expanded theories adding moral norms. We analyzed mailed survey data using structural equation modeling. We found that subjective norms and perceived behavior control significantly affected deer hunting intention when moral norms were introduced into the model. Attitudes independently significantly affected intentions of deer hunting but have negative relations with the intentions. The study suggested that landowners have positive social pressure and were interested in active management but associated financial burden and risk could be shaping negative attitudes. Keywords Theory of planned behavior ● Theory of reasoned action ● Moral norms ● Prescribed fire ● White-tailed deer (Odocoileus virginianus) 

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5. Dead litter of resident species first facilitates and then inhibits sequential life stages of range‐expanding species

   https://doi.org/10.1111/1365-2745.13586  

   Smith, Rachel S. ; Blaze, Julie A. ; Byers, James E. ; Friess, ed., Daniel ( January 2021 , Journal of Ecology)

   Resident species can facilitate invading species (biotic assistance) or inhibit their expansion (biotic resistance). Species interactions are often context‐dependent and the relative importance of biotic assistance versus resistance could vary with abiotic conditions or the life stage of the invading species, as invader stress tolerances and resource requirements change with ontogeny. In northeast Florida salt marshes, the abundant dead litter (wrack) of the native marsh cordgrass,Spartina alterniflora, could influence the expansion success of the black mangrove,Avicennia germinans, a tropical species that is expanding its range northward.

   We used two field experiments to examine howS. alterniflorawrack affectsA. germinanssuccess during (a) propagule establishment and (b) subsequent seedling survival. We also conducted laboratory feeding assays to identify propagule consumers and assess how wrack presence influences herbivory on mangrove propagules.

   Spartina alterniflorawrack facilitatedA. germinansestablishment by promoting propagule recruitment, retention and rooting; the tidal regime influenced the magnitude of these effects. However, over timeS. alterniflorawrack inhibitedA. germinansseedling success by smothering seedlings and attracting herbivore consumers. Feeding assays identified rodents—which seek refuge in wrack—as consumers ofA. germinanspropagules.

   Synthesis. Our results suggest that the deleterious effects ofS. alterniflorawrack onA. germinansseedling survival counterbalance the initial beneficial effects of wrack onA. germinansseed establishment. Such seed‐seedling conflicts can arise when species stress tolerances and resource requirements change throughout development and vary with abiotic conditions. In concert with the tidal conditions, the relative importance of positive and negative interactions with wrack at each life stage can influence the rate of local and regional mangrove expansion. Because interaction strengths can change in direction and magnitude with ontogeny, it is essential to examine resident–invader interactions at multiple life stages and across environmental gradients to uncover the mechanisms of biotic assistance and resistance during invasion.

    

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