National Park Service U.S. Department of the Interior Project Update Apostle Islands National Lakeshore Bees on the Brink Research at Apostle Islands National Lakeshore

Importance: Pollinators at risk in a changing climate Bees provide a critical ecosystem service, pollination, yet we know little about their abundance, diversity, and distribu- tion across National Park Service (NPS) lands. We know even less about the possible effects of climate change on bee popu- lations. Coastal areas are particularly vulnerable to effects Collecting bees: Pouring the contents from Augochlorella aurata, a common green one of the 30 blue, yellow, and white “bee from climate change, and sand dunes are often hot spots for metallic sweat bee, found in the park. bowls” through a strainer, and then into a rare and/or endemic bee and plant species. Apostle Islands Photo: © 2006-2010 John Ascher plastic bag for storage and shipping. National Lakeshore is one of 48 NPS units that are surveying Methods the distribution of bee species in vulnerable habitats (coastal Both sites were located on the mainland near Little Sand dunes, inland dunes, and alpine areas). The bee species within Bay Visitor Center. The vulnerable site was located in a beach the targeted habitats are compared to bee species found in dune area and the paired common site was less than a kilome- nearby, more common habitats. Comparing these different ter away, in an interior field surrounded by woodland. A habitats within each park will reveal if there are rare and/or transect of 30 small painted bowls spaced 5 m apart was laid endemic bee species associated with sensitive areas which out at each site. Bowls were filled with soapy water and left might be vulnerable to processes such as species loss, popula- open for 24 hours on sunny days, collecting bees which are tion decline, and disruption of pollination networks in attracted to the color. Three samples were taken in July and August, 2010, and three more were taken between May and response to climate change. These areas can then be targeted September, 2011, timed to coincide with peak bee activity. for future monitoring, and where appropriate, for active After each run, bees were collected (see photo above) and sent management. to a central processing facility at Patuxent Wildlife Research Sampling Location Center (USGS Maryland) for identification.

Apostle Islands Picnic area Campground, NationalMeadow Lakeshore Site not NationalPark Service Dune Site Dune Site on the mainland near Apostle Islands Trailhead NationalPark Service National Lakeshore, L LAKESHORE Little Sand Bay Visitor TIONA Backcountry Campsite(s) Gaylord Nelson NA Center Wilderness ND LA Bear IS LE Island ST Outer O Island AP A P O S T L E

LighthouseSand Island Bay Oak StocktonI S L A N D S YorkIsland Island Island Raspberry Point Island Meadow Site SandIsland Little Sand Bay Detour in an interior field Visitor Center surrounded by woodland MADELINE ISLAND on the mainland near Summer only Hokenson Fishery Little Sand Bay Visitor Kayak launch Raspberry Center Bay Raspberry Little Point Sand LAKE SUP ERIOR Bay Rd RED CLIFF INDIAN RED CLIFF Trail RESERVATION Frog Bay K I ND IAN

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Bees on the Brink 1 www.nps.gov/apis/ Results A total of 206 bees were collected in 2010 and 2011. Sampling Dates 07/20/10 08/06/10

Approximately three times as many bees were caught in the 08/16/11 08/23/10 2520151050-5-10-15-20 common meadow site as in the vulnerable dune site (150 and 09/02/11

56 individuals, respectively). In addition to trapping more 05/25/11 individuals, the meadow site also yielded more species (32) than the dune site (23), perhaps a reflection of greater plant and therefore pollen diversity in surrounding habitats. Seven species occurred at both sites (see bar graph below). Overall, although species composition differed between

the two sites, the bees collected in Apostle Islands National (°C) Temperature

Lakeshore represent a fairly typical fauna of northern climates, 30 Year Average Avg. Monthly Temp. 2010-2011 with few sand specialists. One species found only at the dune Min site, Lasioglossum pictum, is always associated with sandy Max habitats, but is not considered a dune specialist. The mason bee, Osmia michiganensis, found only at the meadow site, is MJSNJMMJSNJAODFAJAOD 2010 2011 associated with dunes, however, the taxonomy of this group is Month Average monthly min/max temperatures compared to the currently under revision, and so the true identity of the single 30-year average temperatures for the six 2010/2011 bee specimen is currently suspect. The lack of distinct dune fauna Data source: PRISM Climate Group, Oregon State University, http://prism.oregonstate.edu, created January 2011. may not be surprising in this park, as open sandy habitat is limited to narrow strips in bays and at stream outlets. Two species of interest from the survey are Stelis labiata (found at the dune site) and Pseudopanurgus albitarsis (found at the meadow site). Stelis labiata is a rare nest parasite, most likely of one of the Osmia species. Nest parasites, or “cuckoo bees,” lay their eggs in the nests of other species, and the developing young cuckoos kill the host eggs or larvae then consume their pollen provisions. Pseudopanurgus albitarsis is also an uncommon species, and is likely a pollen specialist Coelioxys rufitarsus, a “cuckoo bee” that lays its eggs in the nests of leafcutter bees, of plants in the Asteraceae family. where its larvae kill the host larvae and eat their pollen supplies. Photo: © 2012 The President and Fellows of Harvard College Comparison of bee species richness within genera in dune and meadow sites in Apostle Islands National Lakeshore

Dune Site Andrena Meadow Site

Lasioglossum pictum, a sand-associated Anthophora species found at the dune site. Photo: © 2010 Packer Collection at York Ceratina University, York University Colletes

Nomada

Stelis

Lasioglossum

Bombus

Melissodes The female leafcutter bee, Megachile relativa, collects pollen on the Halictus underside of her abdomen. She constructs brood cells with pieces of Osmia leaves or petals that she cuts with her Megachile large mandibles. Photo: © 2010 Tom Murray Ancistrocerus Augochlorella # sand specialists Hoplitis # species within genus Hylaeus # species unique to dune or meadow site A tricolored bumblebee, Bombus ternarius, Pseudopanurgus found at the dune site. Photo: © 2010 Tom Murray 20 15 10 5 0 0 5 10 15 Number of Species Bees on the Brink 12 www.nps.gov/apis/