Appendix D. Life table response experiment (LTRE) details.

Life table response experiment (LTRE) details

Appendix B. Coefficients for the best-supported model for each vital rate.

Coefficients for the best-supported model for each vital rate

Appendix E. Stable stage distribution and stage-specific reproductive value for tree populations growing in the presence and absence of rodents.

Stable stage distribution and stage-specific reproductive value for tree populations growing in the presence and absence of rodents

Appendix C. Calculating the proportion of variance in λs associated with including the effects of wild ungulates on each vital rate.

Calculating the proportion of variance in λs associated with including the effects of wild ungulates on each vital rate

Data Paper. Data Paper

<h2>File List</h2><div> <p><a href="PLOT_CORNER_COORDINATES.txt">PLOT_CORNER_COORDINATES.txt</a> (MD5: 4a25d9b2196a3d3884ee9adc74322466)</p> <p><a href="RAINFALL.txt">RAINFALL.txt</a> (MD5: f634c991356fcafae5cf8e551bfe19fe)</p> <p><a href="HABITAT_STAKE.txt">HABITAT_STAKE.txt</a> (MD5: 3a23603b67662289dc6531f935bf6697)</p> <p><a href="HABITAT_SQUARE.txt">HABITAT_SQUARE.txt</a> (MD5: 542043d625434817cf2847ba20ed60c6)</p> <p><a href="UNDERSTORY_PIN.txt">UNDERSTORY_PIN.txt</a> (MD5: 90f17f442cfba189eebea0c5d8e46e67)</p> <p><a href="UNDERSTORY_SMQUAD.txt">UNDERSTORY_SMQUAD.txt</a> (MD5: a4b733efcbe76504729d2be1f6a45433)</p> <p><a href="UNDERSTORY_LGQUAD.txt">UNDERSTORY_LGQUAD.txt</a> (MD5: 4ecbacb021cb84562fbe5f28d9d3db28)</p> <p><a href="TREE_SURVEYS.txt">TREE_SURVEYS.txt</a> (MD5: e15589ac0e2e7cfef9a5bccad689ad2c)</p> <p><a href="ACACIA_DREPANOLOBIUM_SURVEY.txt">ACACIA_DREPANOLOBIUM_SURVEY.txt</a> (MD5: acc0f0711e39abc1f8b874c7753fae7c)</p> <p><a href="TREE_CENSUS_SUMMARY.txt">TREE_CENSUS_SUMMARY.txt</a> (MD5: 92e991a3e9f8e84294ff3723c33a508f)</p> <p><a href="TREE_CENSUS_DETAILED.txt">TREE_CENSUS_DETAILED.txt</a> (MD5: dc008f7b72494c9cd861eef7f6093880)</p> <p><a href="DUNG_SURVEYS.txt">DUNG_SURVEYS.txt</a> (MD5: ed5d8079e5db2c0f976d041fd20e87da)</p> <p><a href="SMALL_MAMMALS.txt">SMALL_MAMMALS.txt</a> (MD5: 6e9fcfd6a5d85b25f8d5995a39f46603)</p> </div><h2>Description</h2><div> <p> Assessing the direct and indirect consequences of nonrandom species removal within guilds of strongly interacting species, such as large mammalian herbivores, is an important goal in basic and applied ecology. The ecological impacts of such perturbations are often contingent on abiotic conditions, which have hindered efforts to generalize the results of field experiments. Thus, there is a need for experiments that selectively remove different species from ecologically important guilds and that are replicated across environmental gradients. In 2008, we constructed a series of size-selective large-herbivore exclosures across a natural rainfall gradient in semi-arid Kenyan savanna. This experiment (“UHURU”, for ungulate herbivory under rainfall uncertainty) aims to (a) characterize the effects of successively removing the largest size classes of herbivores from the system and (b) evaluate how the direction and magnitude of these effects are shaped by variation in precipitation regimes. UHURU consists of three electrically fenced herbivore-exclusion treatments and an unfenced control, applied to blocks of contiguous 1-ha plots. The three fenced treatments are: “Mega” (exclusion of elephants and giraffes only); “Meso” (exclusion of both megaherbivores and mesoherbivores, ca. 40 kg and larger); and “Total” (exclusion of all herbivores ≥ 5 kg). Each block of treatments is replicated three times at each of three sites along the 20-km rainfall gradient (increasing from 439 mm/yr in the north to 639 mm/yr in the south, with little background variation in soil attributes and species composition). We present data, spanning 2008 to 2013, from (a) biannual surveys of understory plants at 49 staked grid points within each of the 36 1-ha plots (1764 total stakes); (b) annual woody-plant censuses within the central 0.36 ha of each plot; (c) annual and semi-annual monitoring of individually marked woody plants; (d) small-mammal capture–mark–recapture sessions conducted every other month in total-exclusion and open plots; (e) daily rainfall monitoring throughout the course of the experiment; and (f) quarterly large-mammal dung surveys. </p> <p> <i>Key words</i>: <i>body size; climate; competition and facilitation; ecological field experiments; elephants; extinction; indirect species interactions; Kenya (East Africa); rodents; top-down control; ungulate herbivory.</i> </p> </div

Temporal dynamics in the minimum number known alive of all small mammals in total-exclusion (filled markers) and open plots (open markers) at (A) low-rainfall, (B) intermediate-rainfall, and (C) high-rainfall sites.

<p>Temporal dynamics in the minimum number known alive of all small mammals in total-exclusion (filled markers) and open plots (open markers) at (A) low-rainfall, (B) intermediate-rainfall, and (C) high-rainfall sites.</p

Relationship between two metrics of productivity and rainfall in the six months prior to productivity measurement.

<p>(A) Mean peak understory biomass (grasses and forbs) in two 64-m² grids located within total-exclusion plots at each site. (B) Mean NDVI in each plot, calculated from Quickbird satellite imagery. Rainfall was squared in regression analyses to better fit the data.</p

Mean monthly rainfall (A) within years and (B) across years at each of the three sites.

<p>The asterisks next to years 2008 and 2012 in the top panel indicate that data were available only for 3 and 5 months, respectively.</p

Rate of growth in height (A, C, E) and canopy breadth (B, D) for the three dominant <i>Acacia</i> species across sites and treatments.

<p>Rate of growth in height (A, C, E) and canopy breadth (B, D) for the three dominant <i>Acacia</i> species across sites and treatments.</p

Surface-soil attributes showing significant variation across treatments and/or sites.

<p><b>Notes:</b> Degrees of freedom in 2009 = 3,18 for treatment; 2,6 for site; and 6,18 for treatment*site. In 2010 and 2012, df = 1,6 and 2,6 for treatment and site, respectively, and 2,6 for treatment*site. Levels of treatment and site that do not share the same letter were significantly different in Tukey’s HSD post-hoc tests; the level with the highest mean is represented by letter A, the next highest by letter B, etc.</p