National Pollinator week, June 20-26, 2016

Transcription

1 FOR THE POLLINATORS National Pollinator week, June 20-26, 2016

2 Why the focus on pollinators? 75% of all plants on earth require pollination by animals. For humans: fruits, vegetables, seeds/nuts, fibers, beverages, and many medicines. For wildlife: Natural plant communities that provide essential food and shelter. AND Pollinators are in steep decline

3 2007 Congress established National Pollinator Week. Among the many Whereas statements: "Whereas pollinators help to produce one out of every three bites of food consumed in the United States..." It was a unanimous vote. (!) 2014 President Obama s National Strategy to Promote the Health of Honey Bees and Other Pollinators. Directive to all federal agencies. Given the breadth, severity, and persistence of pollinator losses, it is critical to expand Federal efforts and take new steps to reverse pollinator losses and help restore populations to healthy levels. Addressing: loss of habitat and nutritional resources pesticide exposure pests and pathogens.

4 Basic pollination: Pollen from (male) anther reaches (female) stigma of the same plant species. Egg cells are fertilized in ovary at base of pistil. Seeds form reproduction progress. Cross-pollination, from one plant to another, produces stronger plants. Most plants have stratagems against self-pollination.

5 Nature s mutualism at work: Plant takes care of its pollinator, providing nectar and pollen; Pollinator takes care of preferred plants by enabling them to set seed for the next generation. Flowers deliver just the right amount of nectar reward: too much, insect fills up and stops; too little, it moves on to another plant type. Flowers don t need nectar. They produce it to lure their pollinators. For their part, most pollinating insects and ALL bees are efficient, specializing in one plant type at a time. Therefore: Goldenrod pollen gets delivered to goldenrod, clover to clover, etc.

6 Some pollinators, like squash bees, really specialize. Adults emerge early in season Active early in day Males hang out 24-7 near blossoms Mating occurs within blossom Photos by Hadel Go

7 Some plants and animals evolved together. Larry Master photo Cardinal flowers: Red!! Tubular shape. Bloom when hummingbirds double their weight for migration; Bird s forehead touches anther on male flower collecting pollen that gets transferred to a female flower whose stigma is positioned just right. Cardinal flowers and ruby-throated hummingbird have same range.

8 Just as monarch butterflies need milkweed to survive... other species need a certain larval host plant to survive. + Butterflies aren t Top-10 pollinators, but their population trends indicate trends for other pollinating insects. Monarchs in the last decade lost 100 million acres of wildflower habitat to Roundup ready cropland. Corn and soy grow but the herbicide kills weeds including milkweed. 8

9 The top pollinators are... THE BEES

10 Busy as a (native) bee Honey bees, introduced by European settlers, are the celebrated pollinators, but hardy native bees are more important, especially in springtime cold when honey bees stay in their hives feeding on honey reserves. Bumble bees pollinate 15% of all crops in the U.S. including tomatoes and a few other plants that are a challenge for other pollinators. Through "buzz pollination" ( sonication ), they vibrate pollen loose. Their larvae in underground nests feed on protein-pollen mixed with nectar and saliva ( bee bread ). Common eastern bumble bee / Bombus impatiens

11 Of 18 bumble bee species once found in N.H., 10 remain four of which are Species of Greatest Conservation Need.

12 N.H. is home to over 200 native bee species. Most are solitary bees. One female produces one brood, alone in her nest, laying eggs in cells she provisions with a pollen/nectar mix. Honey bees and bumble bees are social bees. A queen produces several broods with help of worker bees throughout the season, and therefore are top pollinators. The two most common bumble bees in N.H. A bumble bee nest can produce 50 bees or more.

13 Why are bees such good pollinators? The first bees evolved soon after the first flowers c. 125 million years ago. Discovering that pollen provides protein, they split off from carnivorous wasps to become vegetarian bees. (Wise bees: pollen is easier prey. ) Flowers evolved to entice them through food (pollen and nectar), scent, color, and structure, diversifying along with their pollinators. Most bees are hairy, all the better to transport pollen. Both male and female feed on nectar, although only females take pollen back to the nest. They re active all season long, with social bumble bees expanding in number. Known for flower constancy, they stick with one plant type at a time, increasing odds of cross-pollination. Other pollinators are after nectar only, lack flower constancy, and don t come in contact with pollen as much as bees do.

14 Switching gears Why pollinators are declining? (All the usual suspects) What s being done, and how we can help.

15 New Hampshire Wildlife Action Plan traces bumble bee decline to: Changing agricultural practices that create large monocultures; Use herbicides to kill flowering plants ( weeds ); Decrease edge habitat and undisturbed ground needed for bee nests. Use pesticides that directly kill or impair bees. Transport honey bees and bumble bees for crop pollination, increasing spread of pathogens and general stress. Climate change that alters the timing of flowering, combined with drought that decreases food resources for adults and larvae (drought-withered milkweed impacts monarch butterflies). WAP notes that bee habitat is mostly privately owned, and outreach is needed to encourage best management practices for pollinator habitat.

16 N.H. Wildlife Action Plan continued Neonicotinoids are broad spectrum insecticides that are applied both to foliage and to seeds which absorb them into the growing plant. The insecticide accumulates in nectar and pollen, which bumble bees consume. Use of neonicotinoids has expanded, with many crops and nursery plants receiving treatment. Nursery plants generally are not labeled as treated, and thus end up in gardens even when the gardener is trying to attract pollinators. Exposure to neonicotinoids causes increased queen mortality, reduced movements in workers and reduced storage of nectar (Scholer and Krischik 2014). Spring applications of pesticides cause the largest declines in bumble bee populations as queens or just a few new workers are foraging at that time.

17 WAP recommended actions: Develop a monitoring program for bumblebees. Promote organic practices. Encourage land trusts to conserve farmland whose owners agree to farm organically, and provide untilled and unmown areas for pollinator nesting and foraging habitat. (NRCS support funding is available.) Education, education, education pollinator gardens included (1 st year) Harris Center pollinator garden 2016

18 Growing use of neonicotinoids ( neonics ), systemic pesticides that stay with a plant and can t tell the difference between a plant s pests and pollinators. Growing concern about them (and some bans), too.

19 Moving on... The charismatic mini-fauna

20 Pollinator food thru the seasons SPRING Amelanchier (Juneberry), foam flower, willow SUMMER butterfly bush* minerals (soil) dill (host plant) FALL asters goldenrods milkweeds

21 A word (or two) about invasive plants... Vocabulary is important!! INVASIVE plant = a species on a state s prohibited plant list, placed there only after a thorough process. Sale/transport is illegal. Many familiar plants came from other countries. They re classified as ALIEN as compared to NATIVE. Often referred to as INTRODUCED.

22 Of the 4,000+ alien/non-native plant species brought here intentionally or accidentally most fit in with the natural mix of native plants. About 10% do not INVASIVE plants Escaping backyards / gardens into the natural landscape, they spread rapidly, crowding out all other plants to form a single-species mass or monoculture. Characteristics of invasive plants: Thrive in most conditions (shade or sun; wet or dry; different soils). Aggressive root system and/or they produce many seeds. As newcomers, they lack diseases / insect pests / herbivore browsers that kept them in check in their native land. 22

23 Invasive monoculture? or natural biodiversity? 23

24 Join the fun!! 24

25 Pollinators: What can we do? 1. Feed them 2. House them 3. Don t kill them

26 House them 70% of native bees are solitary ground nesters. They require bare ground, untilled and unmulched. The others (mason, carpenter, and leaf-cutter bees) nest in woody material including pithy stems and old beetle tunnels.

27 To help housing? Or recognize bee habitat including nesting and encourage it?

28 Wrapping up Fall in love With butterflies With bees Some people love beetles, also decent pollinators... Go organic (growing and eating) Don t be too backyard-tidy Join/support the Xerces Society and so many other worthy groups Election year: Vote for people who get it