11.8: Data Dive- Island Fox Populations

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Page ID: 46709

Melissa Ha and Rachel Schleiger
Yuba College & Butte College via ASCCC Open Educational Resources Initiative

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Overview

The Island Fox Conservation Working Group and Friends of the Island Fox nonprofit organization work hard to continually fund research and conservation projects to ensure the continued survival of the island fox. In addition, they also have educational outreach programs about the island fox as an endangered species to get public support. Every June the Island Fox Conservation Working Group meets to go over updates and plan for the future. In the 2019 meeting they discussed population trends across the six island fox subspecies and determine what those populations mean for the subspecies trajectory moving into the future. The results of this meeting can be seen in the graph and table below:

Line graph showing population trends for the subspecies of island fox over a ten year period — Figure \(\PageIndex{a}\): Population trends for subspecies of island fox (solid lines = large island subspecies, dashed lines = small island subspecies). Graph by Rachel Schleiger (CC-BY-NC) modified from data in 2019 Island Fox Status Update.

Table \(\PageIndex{a}\): The 2019 designated statuses for the subspecies of island fox based on fox population and island size. Graph by Rachel Schleiger (CC-BY-NC) modified from data in 2019 Island Fox Status Update.

Island	Island Size	Fox Population	Status
San Miguel	Small	171	Concerned
San Nicolas	Small	400	Improved
Santa Rosa	Large	1862	Stable
Santa Cruz	Large	2462	Stable
Santa Catalina	Large	1571	Stable
San Clemento	Small	778	Stable

Questions

What is the independent (explanatory) variable and the dependent (response) variable?
What question(s) are the authors trying to answer with this graph and table?
Which subspecies of island fox do you think is the most stable? Why?
Which year(s) were bad (meaning population estimates were very low) for most of the island fox subspecies?
As noted in the graph, populations are estimated for each subspecies annually. Why do you think an annual estimation was chosen in the conservation plan instead of a longer time interval?

Raw Data From Above Graph(s)

Table \(\PageIndex{b}\): Raw data for population trends for subspecies of island fox (solid lines = large island subspecies, dashed lines = small island subspecies). Graph by Rachel Schleiger (CC-BY-NC) modified from data in 2019 Island Fox Status Update.

Year	San Clemento	San Nicolas	San Miguel	Santa Rosa	Santa Cruz	Santa Catalina
1994	1000	520	450	1800	1500	1300
1996	810	550	100	400	1100	800
1998	650	550	40	100	800	300
2000	800	450	20	50	100	200
2002	450	500	25	60	90	350
2004	450	500	50	70	200	375
2006	400	506	100	80	300	650
2008	400	725	260	100	750	900
2010	900	500	500	350	1050	1000
2012	850	640	525	700	1800	1500
2014	1200	263	510	900	2750	1750
2016	860	329	329	1600	2400	1400
2017	775	255	255	1800	3150	2050
2018	790	400	200	1800	2500	1600

Attribution

Rachel Schleiger (CC-BY-NC)