Salit Kark, Conservation Biology, Hebrew University, Lecture 2 Salit Kark Department of Evolution, Systematics and Ecology The Silberman Institute of Life Sciences The Hebrew University of Jerusalem Conservation Biology (Ecology) Lecture 3 Nov 2009

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 Signed by over 150 governments in 1992 in Rio Became effective as international law in 1993 First international agreement committing governments to comprehensive protection of the Earth's biological resources February 2004, 188 countries and the European Union had ratified the agreement; the U.S. was one of the last nations to sign. THE CONVENTION ON BIOLOGICAL DIVERSITY (CBD)

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 The CBD has three overall goals: The conservation of biological diversity The sustainable use of its components, and The fair and equitable distribution of benefits derived from "genetic resources". THE CONVENTION ON BIOLOGICAL DIVERSITY (CBD)

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 Participating governments agree to carry out various measures to conserve biodiversity: to create national plans for protection of biodiversity. to identify ecosystems, species and genomes important for conservation and sustainable use of biodiversity to monitor biological diversity and any factors that might have impacts on it. to establish a system of protected areas. THE CONVENTION ON BIOLOGICAL DIVERSITY (CBD)

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 Participating governments agree to carry out various measures to conserve biodiversity: to manage biological resources to ensure conservation and sustainable use to rehabilitate and restore ecosystems to take measures for ex situ conservation. The CBD includes agreements for using biological diversity. And governments must provide for "fair sharing" of the benefits derived from genetic resources. THE CONVENTION ON BIOLOGICAL DIVERSITY (CBD)

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 About 92% of plants worldwide are pollinated by animals. There are more than 1200 vertebrate species and between 100,000 and 200,000 invertebrates involved in pollination of flowering plants. 30% of US food supply by volume depends on animal pollinators, of which bee species (Apoidea) are the most important. but most crops in the USA and Australia are pollinated mainly by introduced honey bees. Ecosystem services value Example: Pollination services From: The Nature and Value of Australia’s Ecosystem Services: A Framework for Sustainable Environmental Solutions by Steven J. Cork and David Shelton (2000)

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 The value of honey bees to agriculture in the USA is estimated to be US$2–8 billion annually. Many farmers rely on pollinators of the European honeybee (Apis mellifera) that they import temporarily to crop fields to provide pollination during bloom. Honeybees are not always the most effective pollinators of a given crop, and the number of honeybee colonies, both domesticated and feral, have declined by 50–70% since Example: Pollination services From: The Nature and Value of Australia’s Ecosystem Services: A Framework for Sustainable Environmental Solutions by Steven J. Cork and David Shelton (2000)

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 Example: Pollination services Concern about this heavy reliance on one pollinator species. A “pollination crisis” has been predicted in the US due to a major decline in honey bees caused by a range of diseases and mites. Native, unmanaged bee populations also provide important pollination services to various crops, and are generally more diverse and are abundant near natural habitat It is estimated that other pollinators could take up US$4–7 billion of the service in the USA if they and their habitat were present in sufficient amounts.

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 Example: Pollination services …observed declines in pollination rates and seed set in a range of crops and native plants...possibly associated with less pollination by native bees due to urbanisation, land clearing and modern agriculture.

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 Example: Pollination services Claire Kremen’s study, Ecology Letters, 2004.

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 Example: Pollination services They studied 22 watermelon (Citrullus lanatus) fields located in California June to August Farms varied in the proportion of natural habitat (riparian forest, chaparral and oak woodland) found nearby. Also compared organic and 'conventional' farms In northern California, 28 native solitary and two native social bee species pollinate watermelon Assessed bee visitation to watermelon flowers by walking 50 m of row in 10 min. Estimated the mean total number of pollen grains deposited by bees per flower.

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 Example: Pollination services Kremen’s study: For native bees, mean pollen deposition per flower was significantly related to proportion of riparian or upland habitat no significant effect of farm-type (low power) Model: if farmers were to rely entirely on native bee communities for pollination, their farms would need to be situated in areas containing ≥ 40% of natural habitat within a 2.4 km radius as natural habitat, or ≥ 30% within 1.2 km Both the amount and the stability of pollination services from native bees increased with increased proportional area of upland habitats.

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 Example: Pollination services In Australia, a range of native moths, beetles, flies, birds and marsupials are important pollinators of commercial crops. However, the overall potential for native pollinators to substitute for honey bees is unknown. Declining pollination rates of native vegetation in agricultural landscapes Fragmentation and use of pesticides is having impacts on pollination services in Australia and other areas as well.

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 GeneticDemographic Spatial: (m)population dynamics Conservation biology Population level considerations

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 Relationship between population size and genetic variability Population Genetics and Conservation

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 How do we estimate genetic diversity?

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 נובעת מהעובדה שבלוקוס אחד יכול להיות באוכלוסיה יותר מאלל אחד 2 אללים: a ו- b 3 גנוטיפים: ab,bb,aa תדירות אלל :a p= 8/12= 0.67 תדירות אלל :bq= 4/12= 0.33 תדירות גנוטיפ aa: p 2 = =0.44 תדירות גנוטיפ bb: q 2 = =0.11 אוכלוסיה בת – 6 פרטים הגרלה סטוכסטיות תדירות גנוטיפ ab: 2pq= =0.44 מס' פרטים צפוי 0.44*6= 2.7 מס' פרטים צפוי 0.11*6= 0.7 תצפית: 3 תצפית: 1 תצפית: 2 סטית הנחזה מהצפוי אוכלוסיה קטנה, ולכן מספר "ניסוים" קטן מה תהיינה תוצאות ההגרלה לאחר דור (בהנחה שכל פרט מחליף עצמו בפרט אחד)? הוריאביליות הגנטית Source Uriel Safriel

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 תדירות גנוטיפ aa: q2q2 תדירות גנוטיפ ab: 2pq p2p2 תדירות גנוטיפ ab: תדירות גנוטיפ bb: כאשר תדירות אלל a היא p ותדירות אלל b היא q בהעדר סלקציה תישמר תדירות זו מדור לדור – חוק הרדי-ויינברג אולם שווי-המשקל ישמר מדור לדור רק באוכלוסיות גדולות תדירות הגנוטיפים קובעת את עמידות האוכלוסיה לגורמי ההכחדה האקראית  סטוכסטיות דמוגרפית סטוכסטיות סביבתית סטוכסטיות הקטסטרופות  מקטינות את האוכלוסיה  חוק הרדי-ויינברג קורס  ההרכב הגנטי משתנה  עמידות האוכלוסיה משתנה Source Uriel Safriel

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 כדי לא לאבד אללים נדירים שדווקא הם יסייעו להחלץ מהמצב המסוכן של אוכלוסיה קטנה האוכלוסיה צריכה להיות גדולה הקטנה דרסטית בגודל האוכלוסיה ( קטסטרופה )  הקטנות ב – שעור ההטרוזיגוטיות מספר האללים בלוקוס מרובה - אללים מספר האללים הנדירים שעור ההטרוזיגוטיות כתוצאה מירידה במספר האללים הנדירים מספר האללים הנדירים כתוצאה מירידה במספר האללים בלוקוס מרובה - אללים  עליה בהסתברות ההכחדה צוואר הבקבוק מצב מסוכן עוד יותר אם צוואר הבקבוק מת ארך N גבוה מסוכן לכשעצמו שונות גנטית נמוכה ↓ פגיעות להכחדה כדי לא לאבד אללים מלוקוס מרובה - אללים אוכלוסיה צריכה להיות גדולה N נמוך  שונות גנטית גבוהה  עמידות להכחדה Source Uriel Safriel

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 What is a Population Bottleneck? An observable and dramatic collapse in numbers N TIME RECOVERY CRASH Bottleneck

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 N TIME CRASH INSULAR OR CAPTIVE Bottleneck

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 Whatever the circumstances: a bottleneck is equivalent to taking a relatively small sample of items, in this case genes, from a large population (game…)

Salit Kark, Conservation Biology, Hebrew University, Lecture 2 Loss of genetic variability has multiple aspects specific alleles will either be lost or retained (maintained) genetic variance (or heterozygosity) will be lost