From the 71 pages of administrative logs over this period, Here are the first and last of the 3000 or so offending log entries:

[first:]
Type special
Date Thursday, 15 February, 2007 - 2:47pm
User Editor
Location /admin/node/delete/1936
Message blog: deleted Full Moon Delight.
Hostname 209.222.211.112

[last:]
Date Thursday, 15 February, 2007 - 5:50pm
User Editor
Location /admin/node/delete/4743
Message image: deleted LittleAlyie.
Hostname 209.222.210.222

(Listed time is one hour later than local time)

And here's what the IP lookup returns:

Search results for: 209.222.210.222

OrgName: University of Maine System
OrgID: UMAN
Address: UNET Computing Center
Address: University of Maine
City: Orono
StateProv: ME
PostalCode: 04469
Country: US

ReferralServer: rwhois://named.unet.maine.edu:4321

NetRange: 209.222.192.0 - 209.222.223.255
CIDR: 209.222.192.0/19
NetName: UMAINE-CIDR1
NetHandle: NET-209-222-192-0-1
Parent: NET-209-0-0-0-0
NetType: Direct Allocation
NameServer: NAMEO.CAPS.MAINE.EDU
NameServer: NAMEP.CAPS.MAINE.EDU
Comment: ADDRESSES WITHIN THIS BLOCK ARE NON-PORTABLE
RegDate: 1998-06-05
Updated: 2001-03-12

RTechHandle: IKA-ARIN
RTechName: Anderson, Irelann Kerry
RTechPhone: +1-207-561-3508
RTechEmail: ika@maine.edu

OrgAbuseHandle: NAR5-ARIN
OrgAbuseName: Network Abuse Reports
OrgAbusePhone: +1-207-561-3587
OrgAbuseEmail: abuse@maine.edu

OrgNOCHandle: UNOC-ARIN
OrgNOCName: UNET Network Operations Center
OrgNOCPhone: +1-207-561-3587
OrgNOCEmail: NOC@lists.maine.edu

OrgTechHandle: IKA-ARIN
OrgTechName: Anderson, Irelann Kerry
OrgTechPhone: +1-207-561-3508
OrgTechEmail: ika@maine.edu

# ARIN WHOIS database, last updated 2007-02-14 19:10
# Enter ? for additional hints on searching ARIN's WHOIS database.