mapping global bird distributions

Mapping global bird distributions

NCEAS working group meeting 16-20 July 2001

Walter JetzDept Zoology

Oxford

Benefits

• Large-scale conservation priority setting (refining the hotspot approach with species distributions)

• Rapid assessment of diversity in regions under threat

• Coarse-resolution basis for deductive modelling of species’ fine-scale distributions

• Scrutiny of hypothesis in large-scale ecology

Why a free, public global vertebrate distribution database would be valuable

Mapping Global Vertebrate DistributionsWalter Jetz, University of Oxford

Conservation NGOs• prioritise conservation efforts• taxonomically: range size as

measure of extinction risk• geographically: refining

hotspots using species data

Museums• identify holes in distribution and

gaps of specimen records• prioritise areas for fieldwork• link morphological data and

biogeographic perspective

Academia• identify determinants of patterns in

species richness• detect mechanisms and environmental

correlates of speciation• understand environmental determinants

of biological patterns

General Public• custom species lists for home

region or eco-tourism destinations

Private Sector Land-use• information tool for land

development projects, impact assessments

General GOs and NGOs• tool for resource and land

management

Beneficiaries


Conservation NGOs• ground network of expertise• source and gap identification• facilitation of digitisation and

gap filling

Museums• taxonomic expertise• source identification and selection• specimen records

Academia• methodological expertise• source selection and prioritisation• GIS tools

Joint Effort

Working Groupmeetings at (and funded by)

National Centre for Ecological Analysis and Synthesis, University of Santa Barbara


Diversity of Terrestrial Vertebrates• Birds (Sibley)

– Passerines (Passeriformes): 5879– Nonpasserines (Non-Passeriformes): 4075

• Mammals (Wilson & Reeder 1993)– Platypus, Echidnas (Monotremata): 3– Oppossums, Kangaroos etc. (Marsupalia): 273– Placental Mammals (Eutheria): 4353-78 (whales)

• Amphibians (Duellman & Trueb 1986) – Frogs and Toads (Salientia): 3438– Salamanders and Newts (Caudata): 352– Caecilians (Gymnophiona): 162

• Reptiles (Uetz) – Lizards (Sauria): 4582– Snakes (Serpentes): 2910– Turtles (Testudines): 296– Crocodiles (Crocodylia): 23– Amphisbaenians (Amphisbaenia): 158– Tuataras (Rhynchocephalia): 2

9954

4275

3952

7971

--------26152


State of country- and continent-wide mapping efforts for bird distributions. Dark green: advanced, light green: weak

Birds regional databases

9954 speciesin 176 families


Sources

Identify key sources

Regional atlas projects

Meta-data collections

Museum specimen

Experts’ opinion

Species accounts

Regional species listsCongo Peacock

Square-tailed Kite


America

AustraliaPasserines not covered

Nonpasserines not covered

Europe & Africa

Gridded databases

Not covered

Handbook of the Birds of theWorld

Other Mono-graphs

Birds the knowledge base

I. Major regional atlases(proportion of 9954 bird species)

II. Major monographs(proportion of 176 bird families)


Taxonomically organised sources Distributions

Gaps

Geographically organised sources

source overlap

Inter-relationship of Source Types

• Monographs• Specimen Collections• etc. ...

• Atlases• Regional databases• Regional monographs• Regional specimen collections• etc. ...

• IUCN Red List data • Conservation NGO data and

distribution maps

Sources organised by extinction risk

Taxonomically organised sources

Example: Bird Distributions in Asia

• Threatened Birds of the World• Regional threatened species databases


• HBW - Nonpasserines• Thrushes of the World• Finches and Sparrows of the World• Old World Warblers• etc. ...

• The Birds of China• Birds of the Indian Subcontinent• Birds of Japan• etc. ...


Distributions

Gaps

source overlap

Taxonomically organised sources

Full Distributions



Birds: 9,954 species

I.Handbook of the Birds of the Worldfull ranges for 3,666 species

I.Birdlife: Threatened Birds of the Worldfull ranges for 1,189 species

I.• ABI-CABS Birds of the Americas

Databasepartial ranges for ca. 3,680 species

• Atlas of Birds of Australiapartial ranges for ca. 1,030 species

• Atlas of Birds of Europepartial ranges for ca. 430 species

• Birds of Oceanic islands, from WWF eco-regions and other sourcespartial ranges for ca. 450 species

* listed are potential sources pending agreement with authors/publishers

I. 8,200 species

II.• Birds of the Western Palearctic

full ranges for ca. 520 species• Birds of China• Keith et al: Birds of Africa, Atlases

from Southern Africa, Tanzania, Kenia, Somalia, Liberia, etc. …partial ranges for ca. 2000 species

II. 9,450 species III. Various family monographs

III.• Various regional sources and species

lists.

III. 9,954 species

III.Birdlife: Endemic Bird Areasfor Orientalis, Wallacea

Concatenated,original resolution

How to map a species’ range from a variety of sources?Overlaying disparate sources

Source 1 HBW

Source 2Regional Monograph

Source 3Regional Atlas

Hierarchical Decision Rule

S4 > S3 > S2 > S1

Gridded,fixed resolution

Source 4 Point Data

• Climate and vegetation layers, remotely sensed

• Species habitat preference information

confirmed fine scale presence and absence,extent of occurrence maps for biogeographic validation

Modelled (inductive and deductive) species distribution

General MethodologyRange of potential sources

Identify available sources

Evaluate sources for quality, accessibility and complementarity

Selected sources

Identify most efficient method of digitisation

Digitise

Multitude of regional and taxonomic databases of different resolution and quality

Devise hierarchical algorithm for query where sources overlap

Queried database


Taxonomies

Data Reality• Taxonomies will always differ somehow by expert and region• Various initiatives: ISIS, Species2000…. BCIS

Master Taxonomies ?• Herps: Master Taxonomies?• Mammals: Wilson & Reeder• Birds: Sibley & Ahlquist

Solution …?• Create database of all potential taxonomies (or ask data provider to provide)• Link all taxonomies to master taxonomy

Source Types - Problems

Extent of occurrence maps • poor temporal and spatial resolution• wide coverage• Frame/size of maps printed in books does not scale with extent of range

• potentially high spatial error• size of error should be directly related to map scale, can perhaps be

incorporated in modelling • inter- and extrapolated in unstandardised way, false presences• great resource for range modelling together with point data

Atlas Data• good temporal resolution• geographically limited• differences in observer effort, holes in distribution, false absences

Point Data: specimen, community studies, observations• perfect temporal and spatial resolution• coverage scattered, patchy, biased• great basis for ranges modelling using remotely sensed data and extent of

occurrence maps for biogeographic component

Towards a standardised source database

Fields to include:• Usual reference information (author, year, title, journal/publisher)• Extent: temporal, taxonomic, geographic (description), spatial object• Procedural information: processes undertaken, dates, people behind• Evaluation:

– spatial resolution– quality: correct species identification– quality: spatial error data– quality: spatial error digitisation

• Notes: Similar sources

Source types:• Published or expert-based extent of occurrence maps, atlas data,

gridded databases, regional or local community studies, point localities (observations and specimen)

Square-tailed Kite White-collared Kite

Time Efficient Data Entry

Streamlining the

digitisation process


Ranges of year-round residents, min=1 to max=70 speciesData from Handbook of the Birds of the World, resampled to 200km grid

Global Patterns of Diversity in Diurnal Raptors


Species Richnessnatural breaks, min=1, max=332

Geom. Mean of Range Sizesnatural breaks, min=12990km2,

max=13642403km2

New World Passerines

Collaboration with Lisa Manne and Stuart Pimm. Mapping Global Vertebrate DistributionsWalter Jetz, University of Oxford

Determinants of species richness- Hypotheses -

• Energy availability• Habitat Heterogeneity• Evolutionary Time• Biome area

• Geometric constraints

Plethora of hypotheses

• one single factor ???• many studies to date:

– limited to one specific hypothesis/variable

– limited to small region, taxonomic sub-sample

– limited to one dimension (e.g. latitude)

– excluding the tropics

Lessons so far

Natural breaks classification, 2-615 species per quadrat

Species richness pattern All species (n=1902), continental Africa

Collaboration with Carsten Rahbek.

NDVI mean of all ten-day images (1982-99)

Productivity & Habitat Heterogeneity

• remotely sensed from AVHHR satellites at 7.6km resolution

• NDVI (normalised difference vegetation index) is measure of greenness of vegetation, often used for vegetation classification

• NDVI is synthesis of climatic condition that regulate productivity

Productivity & Habitat Heterogeneityspatial pattern, observed vs. predicted

Natural breaks classification, left 3-558 species per quadrat, right 28-371

observed predicted(NPP, NPP2, HabHet)

Productivity & Habitat Heterogeneityspatial pattern of residuals

Residual from model NPP+NPP2+HabHetStandard deviation classification, <-3 to >+3s.d.; left -8.962 to 8.612 ; right -214 to 262

cyan: -white: 0red: +

A signature of history?

• Past climate events and their potential regional significance difficult to reconcile

• Species data as proxy• Assumption: Regions with restricted range species

(Centers of Endemism) have distinct evolutionary history• Prediction: species richness in such defined regions with

distinct evolutionary history is– likely to be higher than in surrounding regions– much less well predicted from contemporary environmental

variables

Standard deviation classification<-3 to >+3s.d., -214 to 262 species

Natural breaks classification 3-558 species per quadrat

Observed species richness Residual from model NPP+NPP2+HabHet

Centers of endemism: quadrats with species that have <= 10 quadrats range size

The signature of historyobserved and predicted species richness

in and outside Centers of Endemism (CoE)

The signature of historyobserved and predicted species richness

in and outside Centers of Endemism (CoE)

Mean

inside CoE outside CoE

Spe

cies

Ric

hnes

s

0

50

100

150

200

250

300

350

predictedobserved

species withrange size <=10

n = 359 quadrats n = 1379 quadrats

Environmental change and rates of evolution: the phylogeographic pattern within the hartebeest complex as related to climatic variationFlagstad et al. Proc. R. Soc Lond. B (2001) 268, 667-677

Phylogeography


The ‘End’ Product?

One-off database, downloadable from the internet

Continuously updated, peer supervised internet based database embedded in a multi-level access, graphical web-portal with facilities for down- and uploading data etc. ...

Source, species, lat, lon17,1245,45,4217, 1245,45,4317, 1245,45,4117, 1245,44,4317, 1245,43,4317, 1245,43,4217, 1246,02,2217, 1246,02,2217, 1246,03,2017, 1246,03,19………………


mapping global bird distributions

Documents

global bird distributionsnceas

university of oxforddiversity

university of oxfordstate

university of oxfordbirds

bird speciesii

deductive modelling

distribution mapssources

continentwide mapping