? Other biological threats Extinct populations Extant populations - PDF document

Potential consequences of small size and habitat fragmentation on eastern prairie fringed orchid populations Lisa Wallace Potential consequences of small size & habitat Recovery Needs for P. leucophaea fragmentation on Eastern Prairie Fringed Orchid Manage for population persistence ( Platanthera leucophaea ) populations Status and management of pollinators Population restoration Protection against anthropogenic factors Talk Outline I. Ecology of P. leucophaea II. Genetics & rarity Lisa Wallace III. Reproductive biology & rarity Platanthera leucophaea Department of Biology IV. Management trends Eastern prairie fringed orchid University of South Dakota Historical & current distribution of P. leucophaea in the U.S. Exotic species Loss of habitat 1 Purple Loosestrife 12 12 Reed Canary Grass 2 22 9 1 Threats to Prairie Fringed Orchids ? Other biological threats Extinct populations Extant populations Over-collecting Life cycle of P. leucophaea P. leucophaea and its pollinators Wind, Water, Earthworms?? Seed dispersal Dormancy Dormancy Sexual reproduction Germination & establishment Perenniality Competition Competition Colonization of new populations Adapted from Bowles, 1983 Photos from USFWS image library. Coastal Training Program Yadon's Piperia Recovery Workshop Elkhorn Slough National Estuarine Research Reserve January 27, 2005 1

Potential consequences of small size and habitat fragmentation on eastern prairie fringed orchid populations Lisa Wallace Life cycle of P. leucophaea 9 8 Seed germination at 7 soil pH Wind, Water, Earthworms?? 6 Pickerel Creek 5 4 3 2 Seed dispersal 1 0 Dormancy Dormancy 100 Soil moisture � Light-inhibited 80 60 � Water-induced Sexual reproduction 40 Germination & � Stimulated by burning 20 establishment 0 � Mycorrhizae-dependent % infected embryos Perenniality 80 60 Competition Competition 40 Colonization of 20 new populations 0 Nov Jan Mar May June July Sept Adapted from Bowles, 1983 Treatment and Seed Age Effect on Germination Stratification Period and Seed Source Effects on Seed Germination 70 50 Treatment Mean % Stage 2 Germination Stage 1 Germination (%) 45 60 No stratification Inoculated 40 8 weeks Inoculated/ 50 35 stratification stratified 30 16 weeks 40 Stratified stratification 25 30 20 15 20 10 5 10 0 0 Abbott Wadsworth Lyons Pooled Seed Source 18 mos. 6 mos. Bowles et al., 2002 Seed Age Bowles et al. , 2002 Life cycle of P. leucophaea Plant 1992 1993 1994 1995 1996 801 F F NF NF F Wind, Water, Earthworms?? 803 F F NP NP NP Status of tagged plants in 804 F F NF F NF Pickerel Creek Population, 805 F F Grzd NF NF Seed dispersal 1992-1996. 806 Grzd F Grzd NF NF Dormancy Dormancy 807 F F Grzd NP - F = flowering plant 808 F F NF NP NF 809 F F Grzd F F NF = vegetative plant Sexual reproduction Germination & 810 F F Grzd NF NF NP = no plant seen establishment 811 F F Grzd NF F Grazed = grazed by deer 812 Grzd NF Grzd NF NP Perenniality - = no data collected 813 Grzd F NP NP NP Competition Competition 814 F F - NP - 815 F F - NF F Colonization of new populations 817 NF NF NP NP NP 818 F F - F F Adapted from Bowles, 1983 Data from J. Windus, Ohio Dept. of Fish 821 Grzd F Grzd F F & Wildlife Coastal Training Program Yadon's Piperia Recovery Workshop Elkhorn Slough National Estuarine Research Reserve January 27, 2005 2

Potential consequences of small size and habitat fragmentation on eastern prairie fringed orchid populations Lisa Wallace Population sizes in Ohio, 1992-1999 6000 Killbuck Wildlife Area 100 2.5 300 Sporadic flowering may 5000 2 be related to: Inches of precipitation 80 No. of Flowering Plants relative to average 1.5 � Soil moisture Number of Flowering Plants 4000 conditions 1 60 � Lake levels 0.5 3000 � Annual precipitation 40 0 � Burning 2000 -0.5 20 -1 1000 0 -1.5 1991 1983 1984 1985 1986 1987 1988 1989 1990 1992 1993 1994 1995 1996 0 Data from J. Windus, Ohio Dept. of Year 1992 1993 1994 1995 1996 1997 1998 1999 Fish & Wildlife Data from J. Windus, Ohio Dept. of Fish & Wildlife Year II. Genetics & Rarity in P. leucophaea Pickerel Creek Wildlife Area 1000 574 2200 5600 900 � How much genetic variation, estimated with neutral 573.5 No. of Flowering Plants Average level of Lake 800 molecular markers, is detectable in eastern populations 573 700 of P. leucophaea ? 572.5 Erie (m) 600 500 572 � Are the levels and structure of genetic variation 400 571.5 comparable to western populations of the species? 300 571 200 570.5 100 � Is there evidence of fragmentation or small population No data 0 570 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 size in molecular genetic variation? Year Data from J. Windus, Ohio Dept. of Fish & Wildlife P. leucophaea populations surveyed for genetic variation Genetic Diversity Compared at Allozyme and RAPD Loci Populations surveyed with RAPD’s Populations surveyed with allozymes & RAPD’s 0.25 80 i c o 70 L Gene Diversity 0.20 c 60 i h p 50 0.15 r o m 40 y l 2 pops. 0.10 o 30 P % 20 0.05 10 3 pops. 0 0 OH MI ME OH MI ME Allozymes Allozyme data are lacking for Michigan & Maine pops. RAPD's 9 allozymes- 12 loci; 7 RAPD primers- 63 bands Coastal Training Program Yadon's Piperia Recovery Workshop Elkhorn Slough National Estuarine Research Reserve January 27, 2005 3

Potential consequences of small size and habitat fragmentation on eastern prairie fringed orchid populations Lisa Wallace Population Size vs. Diversity at RAPD Loci How genetically distinct are populations of P. leucophaea ? A comparison across species & markers 0.7 % Differentiation among populations 80 Index of genetic variation 0.6 % Polymorphic ISSR’s 70 Loci 0.5 RAPD’s 60 r = 0.119; 0.4 P > 0.05 Allozymes 50 0.3 40 30 0.2 Gene diversity 20 r = 0.017; 0.1 P > 0.05 10 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 0 P. P. Other log harmonic mean population size leucophaea 1,2,1,3 ciliaris 3 orchids 5 P . P. integrilabia 4 ,3 blephariglottis 3 1 Wallace, 2002; 2 Havens and Buerkle, 1999; 3 Cowden, 1993; 4 Birchenko, 2001; 5 Case, 2001 Conclusions- Genetic Variation in P. leucophaea Genetic vs. Geographic Distances Allozymes and RAPD’s suggest different levels of genetic diversity in P. leucophaea. 300 Geographic Distance (km) Allozyme & RAPD loci follow different evolutionary trajectories 200 Both data sets also detected significant structure among populations. Is this a consequence of its current rarity or an indication of its ancestry? 100 Population structure Loss of alleles due to genetic drift and/or fixation of alleles in isolation 0 Population history Founder effects and associated loss of diversity 0 .2 .4 .6 .8 1.0 Origin from divergent source populations and fixation of alleles Genetic Distance from RAPD’s Maine population excluded; r = 0.467; P > 0.05; Mantel test Yes, they are useful because… Is reduced genetic variation likely to lead to population extinction? Are these results useful to the preservation of this species? � They demonstrate the importance of using multiple criteria to judge the worthiness of populations for preservation. � The finding that diversity is not correlated with population size is, perhaps, a positive indication that genetic diversity can be maintained in smaller populations. � The identification of genotypic patterns provides a baseline for managers, should they wish to experimentally augment populations. Coastal Training Program Yadon's Piperia Recovery Workshop Elkhorn Slough National Estuarine Research Reserve January 27, 2005 4