Ecological Archives A025-034-A1

Jeffrey F. Bromaghin, Trent L. McDonald, Ian Stirling, Andrew E. Derocher, Evan S. Richardson, Eric V. Regehr, David C. Douglas, George M. Durner, Todd Atwood, and Steven C. Amstrup. 2015. Polar bear population dynamics in the southern Beaufort Sea during a period of sea ice decline. Ecological Applications 25:634–651. http://dx.doi.org/10.1890/14-1129.1

Appendix A (Table A1). Definitions of covariates and covariate combinations (groups) used to model survival and recapture probabilities of southern Beaufort Sea polar bears.

Covariate group

Covariate

Definition

Age0

Age0

Matrix of indicator variables where a 1 indicates an individual (row) was a cub in a particular year (column) and a 0 otherwise.

Age01.23Fem

Age01.23Fem

Matrix of indicator variables where a 1 indicates an individual (row) was a cub (age 0) or yearling (age 1) of either gender, a subadult female (age 2–4), or an adult female (age >4) in a particular year (column) and a 0 otherwise.

Age01.3Fem

Age01.3Fem

Matrix of indicator variables where a 1 indicates an individual (row) was a cub (age 0) or yearling (age 1) of either gender or an adult female (age > 4) in a particular year (column) and a 0 otherwise.

Age1

Age1

Matrix of indicator variables where a 1 indicates an individual (row) was a yearling (age 1) in a particular year (column) and a 0 otherwise.

Age2

Age2

Matrix of indicator variables where a 1 indicates an individual (row) was a subadult (age 2–4) in a particular year (column) and a 0 otherwise.

Age2Fem

Age2Fem

Matrix of indicator variables where a 1 indicates an individual (row) was a subadult (age 2–4) female in a particular year (column) and a 0 otherwise.

Age3

Age3

Matrix of indicator variables where a 1 indicates an individual (row) was an adult (age > 4) in a particular year (column) and a 0 otherwise.

Age3Fem

Age3Fem

Matrix of indicator variables where a 1 indicates an individual (row) was an adult (age > 4) female in a particular year (column) and a 0 otherwise.

BI2006

BI2006

Matrix of indicator variables where a 1 indicates an individual (row) had a home stratum (Home) of Barter Island in the year (column) 2006 and a 0 otherwise.

CA

Home.CA

Matrix of indicator variables where a 1 indicates an individual (row) had a home stratum of Canada (invariant across years/columns) and a 0 otherwise.

Cap-procliv

Cap-procliv

Matrix of time-varying proportions reflecting an individual's (row) tendency to be captured in the years from its initial capture through the preceding year, used to model recapture heterogeneity.  See Appendix F.

Eff-CA

Eff-CA.l

Matrix of indicator variables where a 1 indicates capture effort was low in Canada (invariant across bears/rows) and a 0 otherwise.  Effort was classified as low in Canada in 2001–2002.

Eff-CA

Eff-CA.m

Matrix of indicator variables where a 1 indicates capture effort was medium in Canada (invariant across bears/rows) and a 0 otherwise.  Effort was classified as medium in Canada in 2007–2010.

Eff-CA

Eff-CA.h

Matrix of indicator variables where a 1 indicates capture effort was high in Canada (invariant across bears/rows) and a 0 otherwise.  Effort was classified as high in Canada in 2003–2006.

Eff-US

Eff-US.l

Matrix of indicator variables where a 1 indicates capture effort was low in the U.S. (invariant across bears/rows) and a 0 otherwise.  Effort was classified as low in the U.S. in 2010.

Eff-US

Eff-US.m

Matrix of indicator variables where a 1 indicates capture effort was medium in the U.S. (invariant across bears/rows) and a 0 otherwise.  Effort was classified as medium in the U.S. in 2001–2003 and 2006-2009.

Eff-US

Eff-US.h

Matrix of indicator variables where a 1 indicates capture effort was high in the U.S. (invariant across bears/rows) and a 0 otherwise.  Effort was classified as high in the U.S. in 2004–2005.

Home

Home.BAR

Matrix of indicator variables where a 1 indicates an individual (row) had a home stratum of Barrow, Alaska (invariant across years/columns) and a 0 otherwise.

Home

Home.DEHBTI

Matrix of indicator variables where a 1 indicates an individual (row) had a home stratum of Deadhorse, Alaska or Barter Island, Alaska (invariant across years/columns) and a 0 otherwise.

Home

Home.CA

Matrix of indicator variables where a 1 indicates an individual (row) had a home stratum of Canada (invariant across years/columns) and a 0 otherwise.

Melt-season

Melt-season

Matrix of covariate values with each row containing normalized values of the length of the melt season each year (columns).  See Fig. 2.

Radio

Radio

Matrix of indicator variables with a 1 indicating an individual (row) had an active radio collar in a particular year (column) and a 0 otherwise.

Search

Search

Matrix of covariate values with each row containing normalized values of the approximate number of hours spent actively searching for bears in the U.S. and Canada each year (columns).

Search-US

Search-US

Matrix of covariate values with each row containing normalized values of the number of hours spent actively searching for bears in the U. S. each year (columns).

Summer-habitat

Summer-habitat

Matrix of covariate values with each row containing normalized values of the area of optimal summer habitat each year (columns).  See Fig. 2.

Time

Time.a

Matrix of indicator variables where a 1 indicates the year 2002 (column) and a 0 otherwise (invariant across bears/rows).

Time

Time.b

Matrix of indicator variables where a 1 indicates the year 2003 (column) and a 0 otherwise (invariant across bears/rows).

Time

Time.c

Matrix of indicator variables where a 1 indicates the year 2004 (column) and a 0 otherwise (invariant across bears/rows).

Time

Time.d

Matrix of indicator variables where a 1 indicates the year 2005 (column) and a 0 otherwise (invariant across bears/rows).

Time

Time.e

Matrix of indicator variables where a 1 indicates the year 2006 (column) and a 0 otherwise (invariant across bears/rows).

Time

Time.f

Matrix of indicator variables where a 1 indicates the year 2007 (column) and a 0 otherwise (invariant across bears/rows).

Time

Time.g

Matrix of indicator variables where a 1 indicates the year 2008 (column) and a 0 otherwise (invariant across bears/rows).

Time

Time.h

Matrix of indicator variables where a 1 indicates the year 2009 (column) and a 0 otherwise (invariant across bears/rows).

Time

Time.i

Matrix of indicator variables where a 1 indicates the year 2010 (column) and a 0 otherwise (invariant across bears/rows).

Time-cubic

Time-cubic.lin

Linear component of annual time (year), with 2001 being defined as 1.

Time-cubic

Time-cubic.quad

Quadratic component of annual time (year^2), with 2001 being defined as 1.

Time-cubic

Time-cubic.cube

Cubic component of annual time (year^3), with 2001 being defined as 1.

TS-sur

TS-sur.a

Matrix of indicator variables where a 1 indicates an early period, 2001–2003, and a 0 otherwise (invariant across bears/rows).

TS-sur

TS-sur.b

Matrix of indicator variables where a 1 indicates a middle period, 2004–2006, and a 0 otherwise (invariant across bears/rows).

TS-sur

TS-sur.c

Matrix of indicator variables where a 1 indicates a late period, 2007–2009, and a 0 otherwise (invariant across bears/rows).

UA

UA.Age01.3Fem

Matrix of indicator variables where a 1 indicates an individual (row) with a home stratum of Canada was a cub (age 0) or yearling (age 1) of either gender or an adult female (age > 4) during any of the years 2007–2010 (column) and a 0 otherwise.

UA

UA.Age2

Matrix of indicator variables where a 1 indicates an individual (row) with a home stratum of Canada was a subadult (age 2–4) during any of the years 2007–2010 (column) and a 0 otherwise.

UA

UA.Age3Male

Matrix of indicator variables where a 1 indicates an individual (row) with a home stratum of Canada was an adult male (age > 4) during any of the years 2007–2010 (column) and a 0 otherwise.

US

US

Matrix of indicator variables where a 1 indicates an individual (row) had one of the three home strata in the U.S. (Home.BAR or Home.DEH or HOME.BTI) (invariant across years/columns) and a 0 otherwise.


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